Heidi Montag: 'I Wish I Could Go Back to the Original Heidi'

Nov. 22, 2010— -- She was once reality TV royalty as a beloved star of MTV's "The Hills," but now Heidi Montag is probably more well-known as the queen of plastic surgery.

"I want to be happy," the 24-year-old said. "I've always heard you can't change the world until you change yourself and who you are."

Montag's shocking transformation after going under the knife for a marathon of at least 10 plastic surgery procedures in a single day last year has turned her from Hollywood starlet to tabloid target.

In a recent interview with ABC News' Cynthia McFadden, Montag said she feels like she's a prisoner in her own made-over body -- a complete backtrack from the "no regrets" position she had in an interview with ABC News' Juju Chang earlier this year.

In 2005, Montag was a fresh-faced 19-year-old from the mountains of Colorado before she was cast on "The Hills." Even before she became obsessed with her looks and posed to remodel her face, Montag was already the center of tabloid white noise and gossip. That kind of attention was new to her.

"It really got to me what people would say about me, and saying I had a horse face, and a Jay Leno chin," she said, "just awful, really mean things about me. ... I kind of started believing it."

Her sudden fame and the pressure of trying to compete with the other girls on "The Hills" helped push Montag to believe that radical re-invention was the only way to go.

"I got really insecure once I got immersed into Hollywood. A lot of girls my age get almost as much surgery, I would say, as me. ... All these celebrities have different faces. Nobody calls them out because they don't talk about it," Montag said, adding that talking publicly about her surgeries was a mistake.

"I shouldn't have talked about it because it just opens it up for everyone," she said.

A big topic of discussion has been Montag's breasts. In 2007, a semi-clad Montag posed for Playboy. It turned out to be a pivotal moment in her transformation.

"That was before my surgery. ... They digitally enhanced my breasts," she said. "That was one of the biggest insecurities I had -- that all these people in a room were telling me, 'No, your breasts aren't big enough."

Montag then became more determined than ever to look Playmate-ready.