Singer Katy Perry fell into deep depression after her album Witness flopped last year. The pop star told Vogue Australia that the public's reaction to her fifth record, which featured the tracks Swish Swish and Bon Appetit, left her heartbroken and led to some serious soul searching, reports aceshowbiz.com.

"I have had bouts of situational depression and my heart was broken last year because, unknowingly, I put so much validity in the reaction of the public, and the public didn't react in the way I had expected to," she said.