Third eye headache

I used to get frequent, horrendous headaches when I was a kid and younger adult. They mostly stopped sometime in my mid- to late-30s. As a connoisseur of headaches, I found the following factors tended to cause headaches for me:

1. Too much sugary food at one time. Solution: Cut way down on sugar.
2. Chronic infection/inflamation. Sinus headaches were the major factor here. Solution: Take pseudoephedrine and ibuprophen, get some exercise to clear sinuses and restore immune functions.
3. Illness - viral infections such as flu or cold. Sometimes viral infections are so subtle you're not even aware your body is fighting them, except for the symptom of headache and possibly some feeling of tiredness.
4. Fatigue - solution: get more sleep.
5. Over-exercise, resulting in lactic acid accumulation in muscles, resulting in aching muscles, tiredness, and headache.
6. Dehydration
7. Bad nutrition

I went to a doctor once when I was having headaches really badly. He did all kinds of tests, found pretty much nothing, and finally the only advice he could give me was, "Avoid stress." My headaches improved after I started becoming more observant about cause and effect and took responsibility for my own health.