What Causes Daily Headache Along With Nausea?

Question: I often get headache almost every day barring few days in a month.and this is happening since a long time almost few years. I have gas problem, untimely sleeping habits, late night laptop exposure and XXXXXXX exposure, also it happens when i change my routine food. instead of chapati if i take rice in the night etc.
most of the time my headache is on the top of the head and at the top back of my neck where it meets the skull. most of the time it keeps shifting from one part another, between eyebrows or behind eye balls. most of the time i feel nausea during headaches. but i can face tv computer or XXXXXXX screens during the headaches.
fed up with this i once got admitted to XXXXXXX hospital XXXXXXX where i went through various investigations like MRI blood tests urine test eye test eyc.

some times i vomit after drinking lot of hot water and it gives some relief but most of the time i get relief only with dart or other otc medicines. tab gives me relief for around 2-3 days and then mild headache starts again. the day i go out in sun for 10-15 mins with inadequate sleep or without breakfast i get a deadly headache 100% for sure in the evening. so with so many triggers and symptoms I am unable to get the main cause of headache. kindly suggest few tests which can be done to know the real cause and the real problem.