Amy Schumer talked about a lot of fun, funny things in her interview with Marie Claire for their August issue; her story of losing her virginity wasn't one of them. Apparently, it happened without her consent, and though she doesn't call it rape, it wasn't consensual:

My first sexual experience was not a good one. I didn't think about it until I started reading my journal again. When it happened, I wrote about it almost like a throwaway. It was like, And then I looked down and realized he was inside of me. He was saying, 'I'm so sorry' and 'I can't believe I did this.'

Sources: h/t Huffington Post