From PEOPLE Magazine Click to enlarge
She's a pop princess, but Britney Spears has recently taken a keen interest in rock. A five-carat rock, to be exact. Set atop two slender platinum, diamond-encrusted bands worn on her left ring finger. And yes, it means what you think it means. Last week the singer, 22, confirmed that she is engaged to her boyfriend of nearly three months, dancer Kevin Federline, 26, and she's delighted. "I'm feeling everything," says Spears as she nestles in Federline's lap. "I'm excited. Elated. Happy. I wake up in the morning, look at that ring and think, 'Very cool.' "

Federline has already won the blessing of his future mother-in-law. "They have good karma," says Lynne Spears. "I think they're a good fit." As for things moving a little fast, she adds, "You can't put a time schedule on relationships. My best friend got married within six months, and they've been together 28 years. It's all a risk." While Spears and Federline won't disclose a wedding date or any details just yet ("I want to keep a few things under wraps," says Spears), they did sit down with PEOPLE senior editor Todd Gold to discuss their relationship, her ring and how all this happened.

Britney: It was about three weeks ago, and we were on an airplane to New York from Ireland. I'd finished the European part of my tour and I was going home. I was ready to get back to the States. I was really happy. Kevin was with me, so I'd had a lot of fun on the tour.

We were a couple hours into the flight, and we'd been talking the whole time, stuff about life, wanting to have kids, the future and everything like that. It was an intimate conversation. And we'd always talked about how some people don't have to get married when they're in love.

Kevin: You can spend the rest of your life with each other if you're in love.

Britney: Then all of a sudden I said, "What if you want to get married?" And I kind of went from there to asking him if he would marry me. I asked him.

Kevin: And I said no.

Britney: He said no because he thought it wasn't the right way to do it.

Kevin: It wasn't like a "Will you marry me?" It wasn't that straightforward. The way she said it was kind of beating around the bush. Still, I was taken by surprise. I thought the guy was supposed to ask the girl. So a couple minutes went by and then I asked her.

Britney: But I'd been rejected and I was a little put off. [She laughs] No, not really. I kind of knew he was going to come back and ask me. And I said yes, of course.

Kevin: My head was spinning. Oh my God, I was happy. I wasn't really thinking about asking her right away but I did without reservation. I'd known for a while that she's the one.

Britney: Oh baby. [She kisses him] Really?

Kevin: Yeah.

Britney: Baby. [More kisses] But I wasn't even thinking about doing something like this because of the big stink that had happened in Las Vegas [she wed Jason Alexander in January, then had the marriage annulled 55 hours later]. I had no idea it would become that big of a deal. That thing was a total ugh. I was not in love at all. It was seriously my friend from home and we got crazy in Vegas.

So marrying Kevin was the last thing I was thinking about doing. But then I said, "You know what? This is my life and I don't care what people think. I'm going to get married. I'm in love with him."

We didn't tell anyone till the next day. First I told my assistant Felicia. Next, I told my mom. I was very nervous, but I knew this was what I wanted to do. I was just a little nervous about sharing such a big feeling. I kind of just told her directly: "Look, this is what I'm doing. I'm engaged and I'm going to get married." She was happy for me.

Kevin: I hadn't even met Mom by that time. I was real nervous.

Britney: Later that day we went on the Internet and started looking for the wedding planner. But I ended up calling my assistant and she hooked me up with someone, and I started planning right away.

I got my ring about a week ago. The woman doing the planning brought us over a selection to look at. There were about 10 rings. I was going to take my mom's engagement ring for the sake of tradition and change it up a bit so it would be my taste but more sentimental. Then I saw this ring. It's kind of spectacular. Even though it's a really big diamond, it's still simple and elegant. It's gorgeous and classic.

Kevin: I thought, "Oh my God."

The engagement capped a whirlwind courtship that started in April. Out with some girlfriends during a break from her tour, Spears spotted Federline at Joseph's, a favorite Hollywood club.

Britney: I always sit at the same table. On the far right. In the corner. Where I can see everything. And I saw him. He was just standing there. I was like, "Hi, just come with me."

Kevin: Actually, I'd met Britney before. She just doesn't remember. It was a long time ago, at my first actual dance job. I was dancing with [pop group] LFO, and we were opening for her.

Britney: We saw each other in passing but never really talked. He thought I was cute.

Kevin: Yeah, I did think you were cute. But it just wasn't the right time. I think everything happens at the right time. That's why we met at Joseph's.

Britney: We liked each other right away.

Kevin: There was something about the whole thing.

Britney: A boyfriend was the last thing on my mind. But he was like a magnet. I was being pulled. It was so beyond my control. We stayed with each other for a week. I was supposed to get on a plane to go on tour. I told my mom I didn't want to go on tour. I was like, "I want to stay in L.A."

At the time, I didn't think he'd come with me because we'd just met. Then I was supposed to get on a plane. Then I canceled my flight. I turned the car around, called Kevin and said, "Where are you at?" The next week I was like, "Kevin, get your passport and come out with me."

The pair say they realized they were falling in love in London. But they won't reveal who was the first to say, "I love you."

Britney: I don't want to say what happened. It's personal. Let's just say it was really beautiful and romantic and special between us. This is just deeper. My other loves were like puppy love. They were like practice for the real thing.

When they returned to the U.S., Spears's knee injury during a video shoot brought them even closer.

Kevin: I saw her collapse to the ground, and at first I thought she was joking. It wasn't like she fell real hard. But when I saw her stay down, it shook me up. I kind of freaked.

Britney: I've hurt my knee before, but this time was worse. The initial X-ray didn't show any damage, but I had an MRI, and the next thing I knew I was in surgery. The ironic part is that Kevin met my mother about five minutes before I went into the operating room.

Kevin: I said, "Hi, I'm Kevin. How are you doing?" Then she stayed with Brit, and I went with her brother to breakfast, where he gave me the whole family speech. He told me what to look out for and not to be nervous. It helped a lot. Later on that night I finally got to sit down and talk to her mom. We hit it off from the start.

The injury meant Spears had to cancel the last leg of the tour. During her four months of rehab, she will be prepping a greatest-hits album, due Nov. 16.

Britney: I was ready for a little break. It had been a great tour, but my head wasn't really into it.

Spears shrugs off the tabloid reports that her team worried that she'd gain weight while she's on break.

Britney: You can't always be perfect and skinny. It's sad you get judged like that. I think when people put on a few pounds, it can be a sign of happiness and contentment. Not that I'm going to become some lardass. I like the way I am right now. I don't worry about it. I eat what I want to eat.

While Spears has met Federline's parents, she has not met Kori, the 2-year-old daughter he has with his ex, actress Shar Jackson, who is pregnant with their second child.

Kevin: By [the time I met Britney, that relationship] was already done. I love my children more than life itself. If there's anything I want people to understand, it's that: My kids will always be a part of my life.

Britney: I plan to meet his daughter. I love little ones. I think the situation is good.

What about children of their own?

Britney: I'm not pregnant. [But] I definitely want to have some kids. I see myself with four or five.

Kevin: I'm not going to say if it'll be soon.

Britney: We're starting with a dog. I just got a Maltese named Lacy.

Anything else going on?

Britney: Here's something new. I love cleaning. I really do. I'm like Suzy Homemaker. I'm starting to learn how to cook. He's a really good cook. He can cook anything—macaroni and cheese, fried chicken. I'm learning how to make all my mom's salads.... I love it. Cooking and cleaning. What's with me?

Kevin: I'll mess the whole place up and she'll clean it up. Really, I help.

Britney: You cook, baby.

Kevin: We don't really watch TV. I can sit and talk all day. That's what I love to do.

Despite this image of domestic bliss, a lot of people might think they're rushing into marriage. What do they say to those who think it's too fast?

Britney: I say I'm sorry you don't have what I have. I knew instantly. I kissed a bunch of frogs and finally found my prince. I feel like I've found my happily ever after.