Singer Katy Perry says she still gets unnerved about performing in front of a large crowd and admits she often feels sick before going on stage.

The 25-year-old star says her stage fright was the reason behind a tearful breakdown at the Radio 1 Teen Awards here over the weekend, reports contactmusic.com.

"I was emotional before I sang 'Firework'. I got chills and butterflies - it's a huge adrenaline rush. All the hairs stick up on my body and sometimes I don't even have to sing because the crowds sing it louder," said Perry.

"I still feel nervous performing to crowds. It's not that I don't feel ready but I worry that they'll rush the stage as they're all screaming my name or I feel like a wanna yack," she added.

Perry, who recently married British comedian Russell Brand, had previously admitted to being self-conscious.

"Even the most confident people still have their moments of insecurity. And even though I may come across as loud and bubbly and brimming with confidence, I can be a shy girl too."