Severe Menstrual Cramps and Bleeding: What Should I Do?

Since I was 15, I've always had problems with my period. My first period was fine, but when I got it the next month, I bled for 6 months straight. Doctors made me use the dwpo shot first and it made me bleed more. I then used birth control pills and it seemed to regulate it. I stopped using the birth control pills cause I wasn't sexually active and everything was fine. But then couple years later my mom made me get the IUD which for one hurt really bad but then I started getting ovarian cysts so I had it removed. I didn't get another cyst but now I get severe cramping weeks before my period and I get my period 2-3 times a month and they're super heavy and I bleed through super plus tampons within an hour. They've done ultrasounds and always say everything is fine but you don't just have severe cramping and bleeding constantly for no reason. my mother had endometriosis but they told me the only way the could test for it is through surgery. what should I do?