Karina Smirnoff has two reasons to get festive on New Year’s Eve: The start of 2013 on Tuesday, with a blowout Studio 54 themed party at the Catalina Hotel, then the next day it’s her 35th birthday.

Not as ideal as it sounds to be born near a holiday.

“When I was younger my friends and I would celebrate the night of Dec. 31 and then finish by the morning of the 3rd,” she says from Los Angeles. “But now sometimes people are too overpartied. They’re like, ‘Oh, it’s too close to New Year’s Eve. We need to do something chill. We’re still recovering!’ ”

The Dancing with the Stars pro also gets occasionally cheated out of good gifts.

“What’s this combined-present thing?” she says, laughing. “You can’t go that route with me. I can understand the thought process, but you need to go all out. Don’t double it. Triple it!”

As fantastic as Smirnoff looks, she also isn’t crazy about aging: “A lot of people say, ‘Oh this is so exciting.’ No! It was exciting turning 25. Counting how many years you’ve been alive? I don’t like that at all.”

Jokes aside, Smirnoff sees good things in our collective futures.

“There was that whole mess with 12-21-12 and everyone expecting the world to be over. I feel like this year is going to bring adventures. It should be about new energy, not the end of something.”

Like the start of yet another cycle of Dancing with the Stars. Smirnoff, who won the mirrorball trophy with soap star/veteran JR Martinez in season 13, is pumped.

“We’re going to start rehearsals up again relatively soon,” says the native Ukrainian who moved to Bronx, N.Y., with her family as a teen. “The rumor is the cast is pretty incredible. I’m excited to see who is doing it and who’s not.”

That means getting into top ballroom shape.

“I work out a lot, but the holidays have definitely been putting an effect on my body,” she admits. “I went running the other day, and after about seven minutes I said, ‘Wow, this seems like a lot of work! I shouldn’t be this tired!’ Getting into shape is way harder than getting out of shape!”

Among her guilty pleasures? Dark chocolate.

“I don’t go one day without having a little bit. But then I usually want something salty afterward. It’s a vicious cycle.”

Madeleine Marr

Gerry Kelly’s Studio 54 party will feature a premium open bar from 8 p.m.-midnight, hors d’oeuvres, dinner buffet and Latin funk courtesy of the Spam Allstars. Catalina Hotel & Beach Club, 1756 Collins Ave., Miami Beach; Tickets $95, VIP tables $900-$1,500.