So I have had my period for a while and every time I have it I have these severe pains, not like every other woman how they have average cramps/pain. But this sort is definitely not normal, so my problem is that my back swells up, it feel like 5 big knives are stabbing me in my pelvis, I get headaches now and then, sometimes I can't even move propaly and other times I'm on the floor, crying or I look Dreadful/nearly dead. And Treatments like stretching/exercise/heat packs/tablets don't always work for me. I want to know what this sort of medical thing is?