17 years old with chronic migraines

I am 17 years old and I have been suffering with migraines since I was in grade school, but just this year I got diagnosed with chronic migraines and got a referral to a neurologist. None of the prescription meds seem to work, and whenever we tell them that, all they do is increase the dosage.

Just recently I had a three week period of severe migraines during which I missed school, so now my school wants to drop me from all my classes, and my neurologist wont write me doctor's notes, so I might not be covered by my parents insurance as a student for meds and such, and they have dropped my case...