How Can Chronic Headaches Be Treated?

i am 55 years old female.i get serious headaches whenever either i am exposed to sun(heat) or i have gastric problem. When i have gastric problem,nights are very painfull with headaches.when i go to bed , i feel normal but middle of the night i feel severe headache and it feels like the gas has gone into the brain. i start vomiting and its continue 6 to 10 hrs.please suggest what to do ?