Kourtney Kardashian Is Keeping Baby Name Options on Her Cell

By Sara Hammel

04/09/2012 at 07:10 PM EDT

Kourtney Kardashian, who's expecting her second child (a girl!) with boyfriend Scott Disick in July, says she feels great – but has discovered a few new challenges her second time around.

"I feel really good ... [though] this time I had a little more morning sickness," she told PEOPLE Monday at the New York City launch of the new Windows phone, the Nokia Lumia 900. "I think it's a little bit harder being pregnant when you have a toddler [son Mason, 2] I'm chasing after. Last time I could nap more."

As hectic as this pregnancy has been, Kardashian says it keeps her on the move.

"I've been active chasing after Mason," Kardashian, 32, says. "We go on walks all the time. Pushing the stroller is like carrying all these weights, and then [there's] the extra weight on my stomach, so it's good. It's fun."

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Still, she says: "Last time I felt amazing the whole [pregnancy], and this time too. I feel really lucky."

She's also putting a lot of effort into choosing the perfect name for her daughter, but says she and Disick haven't settled one yet.

"We always have our little list that I keep in my phone," she says. "I have my little list of names, and I cross it off one day and a new one comes. We definitely don't have the name. We're going back and forth."

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