Is this normal??

During my period I have cramps (in my stomach and lower backk)that are so bad I am literally in tears, I also have headaches that can make me black outt. I am very lightheaded,and sometimes I feel nauseous to the point that I throw upp.Normally I have to take 2 Advil, and a Midol extra strength, and it still hurts it just helps so I can get out of bed,I have tried getting on Sprintec birth controll, it didn't work. I feel like I have been ran over by a semi-truck. My period last 7-12 days, and I can't miss that much school, I talked to my doctor and they didn't think anything was the matter but I don't think I should feel like this.