I've gotten a few migraines in my life. I get them from my dad. Hereditarily speaking, that is. I don't get them very often (touch wood), for which I am very thankful. But I have had them enough to say that I think that the second worst thing about having a migraine (the worst thing about having a migraine is that you're having a migraine) is that people think that they're just really bad headaches, and they're not. They are intense pain which happens to be located in the noggin region, but they're NOTHING like headaches. They hurt more, and differently. There are flashing lights (I believe known as an "aura"). Also, there's sensitivity to light, and to noise, and to moving around. And not wussy sensitivity like "ah, wow, that light makes my head hurt even more," but more in-yer-face sensitivity like "ah, wow, that light makes me have to throw up." This, combined with the moving-around sensitivity, often makes the bathroom floor a difficult place to leave.
Hopefully I didn't fuck with any karmic-type things that make me have a migraine any time soon. That's why I rarely fake migraines in order to get out of work. I'm too afraid of the Migraine Distributer God person.