Selena Gomez thought she had the body of a '12-year-old boy' during her 2016 tour and feared her label would regret signing 'some Disney kid'

• Selena Gomez's new documentary "My Mind & Me" premiered on Apple TV+ on Friday.
• The film opens with old footage from Gomez's 2016 "Revival" tour, which was canceled after 55 shows.

Selena Gomez opened up about her mental health journey in her new documentary, "Selena Gomez: My Mind & Me," which premiered on Apple TV+ on Friday.

The intimate film, which was filmed over several years of Gomez's life, opens with footage of the young star during rehearsals for her 2016 "Revival" tour.

During outfit fittings, Gomez openly struggled with her reflection and poked fun at her own body, noting that if she were a male singer, "I could wear jeans and just switch up my T-shirt and put a beanie on and nobody would care."

"I wanna have the body to wear it proudly. I want the booty that I don't have. My body is very young," she remarked while watching a video of herself onstage, adding, "Making sure I look like a woman and not like a 12-year-old boy."

After Gomez completed her final rehearsal, she broke down in tears and fretted about her capability as a performer.

"It just sucks, all of it. It looks so bad. I have no idea what the fuck I'm doing," she told her friend Raquelle Stevens. "So I get the voice that comes in my head that says, 'You missed this, that sucked, that sucked.' Oh, you get a glimpse of yourself on the screen, 'Wow, that looks pretty fucking shitty.'"

"It sucks the life out of me and I don't wanna perform," she added. "The pressure is just overwhelming because I wanna do the best and I can."

Despite reassurances from her team, Gomez continued to worry that she was disappointing John Janick — the chairman and CEO of Gomez's label Interscope Geffen A&M Records — because she didn't want him to think "he signed some fuckin' Disney kid."

In the same scene, Gomez mentioned that Janick called her earlier that day to discuss "the song with Justin," presumably Gomez's ex-boyfriend Justin Bieber. (No such collaboration was ever released.)

"I'm like, when am I gonna just be good enough by myself? When am I gonna be good just by myself, not needing anybody to be associated with?" Gomez said.

She also wondered if the show felt too "young," adding, "I would want nothing more than to not be my past, and it comes back."

The "Revival" tour was eventually canceled after 55 shows. At the time, Gomez told People she was struggling with "anxiety, panic attacks, and depression" as symptoms of her Lupus diagnosis. Shortly after, Gomez checked into a mental health treatment facility.

"I wasn't well. That's actually the only answer," Gomez recently told Vulture while reflecting on the 2016 tour footage. "I wasn't well, and I couldn't continue. I had to cancel what I needed to cancel in order to live."

She also said it was "shocking and upsetting" to watch old videos of herself disparaging her appearance.

"I can't believe I was that girl. That breaks my heart. I'm grateful to be on the other side, but when I watched, for example, the first part of the film where I discuss my body — I don't want to cry now, but I was completely upset with myself," she said.

"I couldn't believe the things I was aspiring to be," Gomez continued. "Which really aren't possible unless you have a lot of money and you're willing to spend it to do that to yourself. It really broke my heart. That's not the feeling I want to give anyone. I hope I don't."