Bleeding during sex?

Hi okay so I’m not sure if I should be concerned or not about this. Anyway, so my boyfriend and I were getting into things tonight, and when he pulled his hand away there was blood. I got my period last week, so it wouldn’t be from my period...according to eve ovulation would start around today, but that could be slightly off my last period was a bit longer than normal. I know that it could also be caused by friction which is possible. But we only got as far as fingering, although I guess I could be classified as rough for fingering (sorry for the TMI). I just want to know if I should be concerned or if I should Only be concerned if it happens again.