Demi Lovato says the 'negative' influence of fame caused the 'incident where she hit her backup dancer'

Demi Lovato gives it her all.

In her new documentary Child starwhich she co-directed with Nicola Marsh, the actress/musician (who uses she/her pronouns) reflected on the “explosive” moments that resulted from the negative effects of fame on her mental health.

“I didn't realize it would have such a negative impact on my mental health,” Lovato, 32, said of her experience with fame. “And unfortunately, sometimes that looks explosive, like an incident where you hit your backup dancer on an airplane or you overdose on heroin.”

(In 2010, Lovato punched Alex Welch, a dancer on the Jonas Brothers' tour at the time. The incident prompted the pop star to enter rehab. In 2018, Lovato suffered a near-fatal drug overdose and suffered three strokes and a heart attack while in the hospital.)

The “Cool for the Summer” singer said working on the documentary gave her the opportunity to make amends for her behavior.

“Speaking to people who knew me at a different time in my life was challenging because I wanted to apologize for my behavior,” Lovato said. “I wasn't the nicest person to work with at times because I was struggling so much inside and under a lot of pressure.”

They added that talks with Raven-Symoné and Alyson Stoner in Child star was “really cathartic.”

“They were so kind, so incredible and so open-minded, and I was so grateful for that,” Lovato said.

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In an interview with PEOPLE, the “29” artist spoke about his decision, Child star.

“It was just a story I've wanted to tell for a while,” she said. “I've always thought about exploring the history of child stars and also looking at different points of view and perspectives on what it's like to be a child star in this day and age.”

Lovato added that personally, they have been “very, very honest in the past” and have “shown that vulnerability my whole life.”

“I shared a lot with other people and realized that my experiences don’t define me,” she said.

Child starwhich was published on Tuesday, September 17, contains interviews with stars from past and present such as Drew Barrymore, JoJo Siwa, Kenan Thompson, Raven-Symoné, Christina Ricci and Alyson Stoner reflect on how they dealt with fame at a young age.