After having labor induced, Sweeney, 31, gave birth to Megan Hope Sanov at 11:48 that same night.
Sweeney describes her surprise – and her husband Dave Sanov's mad dash to the delivery room just in time for the birth – in the new issue of PEOPLE, on newsstands Friday.
At home in Los Angeles, little Megan already has her dad, a California Highway Patrolman, "wrapped around her little finger," Sweeney says. Not to mention her big brother, Ben, 4: "He pets her on the head and calls her cutie-pie!"
Pink and Brown NurseryMegan's nursery is decked out in pink and brown tones with sage green accents, a feminine chandelier, and traditional Bellini furniture. Tradition, too, dictated Megan's name: "There have been a lot of quirky, unusual celebrity baby names. But we wanted people to be able to spell it. We wanted it to be more timeless," Sweeney tells PEOPLE.
There's nothing old-fashioned about Sweeney's post-baby workout routine, however. The star who, was back on the The Biggest Loser set just eight days after the birth – and returned to her role as Sami Brady on soap opera Days of Our Lives just six days after that – has been turning to her Nintendo Wii for help. Sweeney is the proud owner of a new fitness program, called EA Active, and has been following its lead to help bust her baby weight.
"When do I have time to go to the gym?," asks Sweeney. "It really is like a personal trainer in a box. It's perfect. I recommend it to all mothers!"