Please help...explain to me somehow?! (4 Girls)?

So my boyfriend and I had one night and all of a sudden my insides hurt...like cramps but it seemed worse and I couldn't fall asleep it hurt so much. Then I'd be fine until we had again. Well a couple of nights ago it was fine when we were having but then when he "thrust" too hard i got that shooting pain again...now i have my period and it seems way lighter than usual...don't know if that has anything to do with the pains during but i thought i'd add that...i'm just a lil confused....and then there was an itty bitty bump under my skin near my hip bone...I need explanations of some sort...please help me out! and then until I got my period (which was on time) i had little cramps like everyday!