Perhaps you have a true intolerance rather than an allergy? If that's the case, amount may be a factor in whether you get a migraine. From what I remember from our allergist was telling us, it takes a few days for dairy to get out of our systems. So while dairy one day may be fine, or tiny amounts of dairy cc might be okay, you add them up over a few days and get whammied.
So if you, say, ate the cheese the day before, like you did this time, and then got just a little bit of contamination in your processed food the next day, that might be just enough to push you over the edge. I know you mentioned not having any dairy ingredients in your food, but could there be traces from dairy cc due to processing, by any chance?
Like perhaps the dairy free bread might have been made on an equipment line or in a facility that does have dairy, so it might get just a little bit of contamination. That sort of thing. Not enough to usually give you a migraine, but maybe with the little bit of cheese the day before, it was enough to zap you, you know?
I can't think of a lot of dairy things that might cause headaches that you wouldn't be noticing with other issues as well. Although cheese mold (that's used to make the cheese) can cause problems with some folks, so it might be worth checking to see if it's any dairy or if it's just cheese.
An elimination diet journal that also records amounts that you are eating might be useful. That was helpful to me when I ended up having an intolerance that was amount based - it IS hard to figure out, definitely! Because you feel like you ate it find one day, and then got sick the next. But if you can track amounts, or types of processing of dairy, perhaps that might have some of the answer for you.
Thanks Shauna! Ya...I'm still confused. I get a migraine usually without fail about 21 hours after eating dairy (mainly cheese)...yet some days where I didn't have cheese or anything dairy the day before I still get a migraine. So I am in the process of doing a daily, in depth food journal. (something I should have started years ago...but better late than never!)
Thanks for the response