Really bad period pain

So to kinda start off about 4yrs ago I had a cyst the size of a cantaloupe removed and my left ovary and Fallopian tube removed. Ever since then I’ve had HORRIBLE periods where I will be in so much pain I would end up in the ER. Sex in certain positions hurts, and sometimes when I’m not on my period I will have bad cramps. The pain is not only cramping its back pain as well and it feels like someone is stabbing me with an inflamed knife. I’ve dealt with military drs who keep passing me along saying oh it could be this or oh it could be this and never really tried to figure out the cause of it. Now I’m dealing with VA drs and they just want to keep trying me on different birth controls. So far none have worked. Does anyone have any idea what could be the cause? I’ve heard Endo could be the cause but I’ve had two kids afterwards and I didn’t have issues getting pregnant which I’ve heard endo causes. Anything will help I’m tired of being in so much pain and feeling like I’m alone and going crazy.