Demi Lovato "thought she would be sick" at her first performance.

The singer-and-actress found fame on Disney show Sonny with a Chance, which she left last year.

Demi, 19, admits that she was not always a fan of being on stage. Her first performance was terrifying.

"I was so nervous that I thought I might be sick, but I was also really excited," she told OK! magazine. "Once I got out there I loved it!"

Demi is now deeply devoted to her flourishing career. The star sets her sights high and is interested in collaborating with some of her favourite artists soon.

"There are so many musicians I'd like to work with," Demi gushed. "I can't name just one. I'd really love to work with Kelly Clarkson, Adam Levine and Eminem. They are all so talented."

Demi went rehab in 2010 to be treated for "emotional and physical issues". She has battled an eating disorder which she's been open about in the hope it will help other young people.

Demi has thrived since being released from treatment.

Her new album Unbroken was released last autumn.