Debilitating Period Pains: Seeking Advice

I've always had really bad period pains. to the point where I'm on the floor unable to move bc the pain is too bad. (i have a relatively high pain tolerance and any time i complain about something hurting, you know its REALLY bad.) but yeah it makes me nauseous and extremely tired. I end up having to take days off from school/work every month bc of how bad it is. I ended up going on birth control about a year ago which stops my period and it's a life saver for me. But, I still get random cramps sometimes (not even close to how bad they used to be) but I'm still concerned. all of the doctors I've talked to about it said "some pain is normal with your period" but I don't think the level of pain I get with a period is normal at all. I've always felt something is wrong/off with my uterus or reproductive system. maybe endometriosis? I don't know what to do next or where to go. should I be concerned? I just need advice or education on what it might be.