What can I do about these severe menstrual cramps?

Sorry i’m new to this, I didn’t know this is where you put the details so here goes….I have severe cramps, yes they are around my period. They double me over and I can’t move, severe pain in my abdomen, pain in lower back, and nausea. Can you suggest why it is so bad? I have severe abdominal pain and pain in lower back, can’t move, can’t do anything for a few hours until tylenol, ibprofen, etc, kicks in. It’s been getting worse over the last few months.