What Causes Blurred Vision And Headache?

had craniotomy with resection of an arterio veinous malformation 3 years ago and have found several bumps on and near area of surgery.I experience several different problems such as after 1-2 hours of standing or moving I feel drained of energy plus sometimes blurred vision head pain but most of all a feeling of pressure like someone were squeezing your skull.yes there is some head pain mainly on the right side of skull. I have seen neurologists and emergency services at hospitals so far no explanation of the bumps or the other symptoms.