is it bad?

So i love having my nipples bit when i have sex but i guess the last time (which was as rough as i could take it, like it "hurt so good") was a little too rough because my nipple started bleeding from the side the next day after a hot shower, idk if it was during sex. My question is, if i continue to do this because it feels good could it be bad or dangerous for me? Literally my fwb said he felt like he was biting off my nipple & for a guy as rough & kinky as him to say that means a lot.