Can Rough Vaginal Sex Lead To Vaginal Bleeding?

I had sex with my boyfriend 3 times yesterday, it may have been a little rough, and I definitely felt some stabs of pain on occasion when he went too deep, or when it got a little dry.

Today I'm having vaginal bleeding, the blood is very red and looks fresh. I am also having dull menstrual type pains - but I already finished my period a week ago. (I am on the pill aswell.)

I am certain I don't have a std as I've only have one previous sexual partner and he was too a virgin. My new boyfriend and I have never had unprotected sex.

What could the bleeding and dull pains be?