It's sometimes a little difficult to tell the difference between migraines and sinus headaches, and I get both. Frequently I have to check the pressure points to know the difference. My known migraine triggers are hormones and stress, but the sinuses? As Em said, it's almost easier to list what doesn't get me going! And after doing something like I did yesterday, mowing the pasture - let's see, there's dirt, pollen, fungus spores, the smell of several relatively strong-smelling weeds, diesel fumes. I feel absolutely polluted.
