I have had a headache for just over a month. Non-stop. Help?

I went to the doctor(s) several times. I have had migraine/tension headaches. They ease up to normal headaches once in awhile, not often. I was given several medications and none of them seemed to work. My doctor today sent me home (homebound from school for the rest of the year) and to take excedrin. My head really hurts. I am sixteen do you think that the doctor is thinking I want out of school? [given i am a straight A emancipated student] I keep getting shunned. I don't know whether to go to another doctor or what. I have been checked for a tumor and been blood tested for abnormalities. What should I do? Suggestions?