Kate Gosselin -- who makes her Dancing With the Stars debut tonight -- is beginning to wonder why she agreed to hit the dance floor in the first place.

"I wake up in a cold sweat every night," the mother of eight, 34, tells USA Today. "What have I signed up for?"

Gosselin, who has zero dance experience, has been practicing with partner Tony Dovolani on a makeshift dance floor in the basement of her family's Wernersville, Pa., home.

"Never danced in public," she says. "It's a huge fear." Overall, her goal is "to conquer my fear of dancing. It's hugely scary."

Her toughest competition? "Me. I struggle with perfection," she says. "While it's fun, I'm frustrated. Tony has to tell me to stop being so hard on myself."

So far, she's had no major ailments, but she says: "There's a sharp pain behind my right rib."

Last week, Gosselin denied rumors she was being a diva on the Los Angeles set and defended her decision to do the show (critics have said she should be spending more time at home with her kids).

Gosselin said doing the show and being a mom is "a delicate balance" and that she is usually dancing "before [the kids] are up in the morning or at school."

She added, "I'm making the best of it."