Icky! I'm so sorry you are going through this. I get tension headaches, which aren't as bad as migraines, but I somewhat feel your pain. Turned out my headaches were related to a lactose sensitivity. There is a website I used to track everything, it is awesome, and was instrumental in helping me figure things out. (I had some other symptoms in addition to the headaches)
Anyways, here is the website:
http://www.foodintol.com/
Check it out! I hope you find something that helps!!
~Heather