I suggest a heating pad and PAMPRIN (not tylenol, that weak stuff doesn't do a damn thing!) for right now.
I also suggest birth control as a long-term solution since it does indeed lighten the flow and lessen pain.
I know how you feel, because I too have extreme period pain. I have also vomited (numerous times) because the pain was so excruciating. I used to have to take pamprin as soon as I noticed cramps because if I didn't, I would be bedridden for 2 hours. I've missed school due to my cramps.
Then I got on Orthotricyclen Lo. The pain became so manageable I didn't even have to take pamprin at ALL!! It was really a godsend after dealing with painful cramps since about age 16 until age 20. Four years of agony once a month... I wish I'd known sooner