I get a headache everyday when i wake up. please help?

whenever i first wake up and first open my eyes, i get a headache. i don't understand why, i feel it at the top of my head in the middle. i already have glasses/contacts, plus it happens within the first minute of waking up so idt its has to deal with my vision. my headaches hurt so bad, i have to take 4 Excedrin migraine to calm it down and sometimes that doesn't even work. why do i keep getting these everyday!?