Hannah Montana may have been the vehicle that launched Miley Cyrus to superstardom, but that doesn't mean the Disney show was a glowing experience for her. As Cyrus graces the cover of the September issue of Marie Claire, she opened up about her experiences as a child actor, which included body image issues, 12-hour days and getting her first period on the set of her hit show.

Cyrus, who got the Hannah Montana gig when she was just 11 years old, said that the show gave her unrealistic standards for what it meant to be both a pop star and a woman in the modern world.

"From the time I was 11, it was, 'You're a pop star! That means you have to be blonde, and you have to have long hair, and you have to put on some glittery tight thing.' Meanwhile, I'm this fragile little girl playing a 16-year-old in a wig and a ton of makeup. It was like Toddlers & Tiaras. I had f*cking flippers," she said. "I was told for so long what a girl is supposed to be from being on that show. I was made to look like someone that I wasn't, which probably caused some body dysmorphia because I had been made pretty every day for so long, and then when I wasn't on that show, it was like, 'Who the f*ck am I?'"

The 22-year-old singer and activist noted that she would be hopped up on coffee all day throughout her developing years and that the stress of being a star would oftentimes get to her before big moments.

"I would have anxiety attacks. I'd get hot flashes, feel like I was about to pass up or throw up. It would happen a lot before shows, and I'd have to cancel. Then the anxiety started coming from anxiety. I would be with my friends, thinking, I should be having so much fun. You get in this hole that seems like you're never going to be able to get out of," she said.

She also admitted that she got her first period while on the set of Hannah Montana while wearing white pants. Her mother, Tish Cyrus, had to put her tampon in and Cyrus immediately had to go back to work.

But now, Cyrus is breaking out on her own. She released her comeback album Bangerz in 2013 and has gone on to found charities, including the Happy Hippie Foundation.

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