Have you had your optic nerves checked for papilledema? Or have you had a spinal tap to check your spinal fluid pressures? There is a disesase called Intracranial Hypertension or Pseudotumor Cerebri. I have it and it was found after I had had a headache for 4 1/2 years. It might be something to check in to. An opthalmologist is someone that could verify it.