The 'I kissed a girl' hitmaker, who was married to funnyman Russell Brand, said she thought her girl friend in school was beautiful, reported the Huffington Post.
"When I was 15, I fell in love with a female friend. I thought she was beautiful and wanted to be like her. She had such a huge impact on my life, but I never told her how I felt," she said.
Perry, 29, who divorced Brand in 2011, also said that she felt bad about two weeks after breaking up with him.
"What I wanted to call this record at first was 'Adult Reality,' because 'Teenage Dream' was me so high on that cotton candy cloud, and then it's like I got punched in the face and kicked down the stairs a couple of times," she added.