It's just a joke, you are overreacting. Am I?

My old friend and I are chatting and he suddenly asks me if "its" still big (breasts). I got mad and told him its not cool. He said he was just asking and its a "joke", told me that I was overreacting. Am I? I literally just wear oversized shirts and jeans and his mind is still fucking dirty, this is why I don't feel comfortable wearing tight shirts even when Im home and alone. Fucking disgusting mind can be.