Growing up in front of the camera wasn’t easy for Demi Lovato.

In fact, the "Cool for the Summer" singer says she remembers little after the release of Camp Rock, the hit Disney Channel TV movie she starred in at age 15 with the Jonas Brothers, which launched her to fame.

"I think I’d passed the threshold of what I could withstand emotionally and physically," Lovato told the Hollywood Reporter in an interview published Aug. 14. “And I didn’t realize that child stardom could be traumatic—and it isn’t traumatic for everyone, but for me, it was."

The 31-year-old, who has spoken about her mental health and substance addiction struggles as an adult over the years, reflected on her past on-set behavior and anxieties as a child star of both the hit Camp Rock franchise and the Disney Channel series Sonny With a Chance, which ended in 2011 after two seasons.

"I think about people in the wardrobe department on my TV show because I’d go in there in bad moods all the time and I worry about guest stars that came on or the other actors or the people during Camp Rock 2," she said, "And it’s easy to excuse that behavior because I was so young and in so much pain, but I’m really remorseful, and that's a guilt that stays with you forever."

Lovato shares more about her childhood fame in her directorial debut Child Star, a documentary about the challenges of early fame that includes her chats with fellow former child stars such as Drew Barrymore, Christina Ricci, JoJo Siwa and Kenan Thompson. The project is set for release Sept. 17.

Meanwhile, the Grammy nominee is in a place in her life where she feels more at peace than she has in years, and are even thinking about starting a family. And if Lovato—who has been engaged to fellow musician Jordan "Jutes" Lutes since December—ends up with a daughter of her own, who wants to follow in her footsteps to pursue a similar career path, she has an idea of what to tell her.

"I’d say, 'Let’s study music theory and prepare you for the day you turn 18, because it’s not happening before that'," the "Confident" artist said. "'Not because I don’t believe in you or love you or want you to be happy, but because I want you to have a childhood, the childhood that I didn’t have. And also, let’s come up with a backup plan.'"