Katy Perry was "humiliated" in "very uncomfortable ways" when she first started in the music industry.

The "Roar" singer had a rough start in music and despite being discovered by super-producer Glen Ballard in 2001, she got a number of knockbacks before finally releasing her major label debut album One of the Boys in 2008, which she says was character building.

"You have to eat dust in the music industry. You'll get humiliated, often in very uncomfortable ways. That period of my life was like a test of my strength. My philosophy is: you get presented with these challenges so you can learn to overcome them," she said.

Katy, 29, has since had the last laugh as her has now become one of the biggest selling pop singers of the last decade with hits including "Teenage Dream" and "California Gurls." The "I Kissed a Girl" star also found her 14-month marriage to British comedian Russell Brand from 2010 to 2011 tough, but put as much effort into making it work as possible. "When I was married I kept taking breaks in between touring so I could dedicate time to my marriage. It was extremely draining, but my marriage was worth it to me," she added.