Heidi Klum gets ‘anxious’ ahead of Halloween costume reveal (Exclusive)

Heidi Klum opens up about her Halloween anxiety.

Speaking exclusively to PEOPLE at the grand opening of Crazy pizza in New York City on Tuesday (October 29), the model, 51, revealed that she gets “anxious” before revealing her elaborate costumes.

“I always get anxious,” Klum says. “Because there’s no real trial. like, I can’t do a real adaptation until I’m in it. Because I never know if it’s going to work until the day (of). And then you know, and then something happens, and I’m like, ‘Oh my god.’ ”

Speaking of a past mishap with her costume, the America’s Got Talent The judge tells PEOPLE: “When I was an apple, you know, Seal and he was Eve.”

“And because I was 9 months pregnant and I wanted to make sure nothing could harm the baby or anything,” she continues. “So I was thinking of being this big apple, but then we forgot how do I get to the party?”

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Klum – who was married to Seal, 61, from 2005 to 2014 – adds: “Look, I couldn’t fit into anything, so I couldn’t get through any normal car doors. So at the last minute they had to get me a the convertible to be able to even get into the car to be able to drive there.”

The German-born star is known for her extravagant Halloween costumes for her annual Halloween party in NYC. Last year, she dressed up as a peacock for her party at Marquee Nightclub.

Elsewhere in her chat with PEOPLE, Klum talked about how her kids like to have creative control over their Halloween costumes.

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The TV personality, who is now married to musician Tom Kaulitz, shares Leni, 20, Henry, 19, Johan, 17, and Lou, 15, with Seal.

“Yeah, I mean, they have their own ideas. I mean, Lou, especially she does her own thing,” she says. “She’s also really into anime. She makes all the wigs herself, like all the pink ones. They don’t just go down.”

She adds: “They have similar points and stuff, so she does it all by herself. She’s quite talented, I must say, more talented than me when it comes to building things.”

“She buys all the accessories and then she puts on a little mask, you know, but like a real one,” the proud mom continues. “She (wears the mask) when she grinds things down and she builds things.”

Klum adds, “So she doesn’t know, inhale all the dust. But she does things … she does them properly. If anyone has that big block about dressing up and stuff, it would be my Lou.”