Many of my friends have not had migraines. Some, despite many years of hearing people complain of them, disbelieve that such things even exist and probably secretly wonder if complaints of migraines are malingering. Even if they accept the good faith of the migraine patient's complaints, they lack the experience to distinguish it from a simple (if intense) headache, and wonder why the sufferer cannot simply take some aspirin or other over-the-counter analgesic medication and go on about their day.
Aside from the nausea, a big distinguishing symptom of the migraine is subtly distortion of sense perception, which is called an "aura." The aura is usually the first signal that a migraine event has begun -- for me, I will see an aura an hour or two before the onset of the pain. This is called an "aura" and last night I stumbled upon a video that does a pretty good job of illustrating what an aura looks like:
I suppose some people have auras that manifest only in black and white; I perceive them in color and more often as parts of my vision upon which I cannot focus, so they seem to be blind spots. If you follow the video's instructions and look at things other than the aura, it remains in your peripheral vision. Other people report different kinds of sensory hallucinations -- my mother gets them, too, and she reports the smell of burned toast in the hours before the pain sets in. While one patient's exact kind of aura may be different from another's, the common thread of aura is hallucination.
The word "hallucination" sounds frightening, as though the migraine sufferer somehow departs from reality, in the manner of a mental illness like schizophrenia. The video should demolish that perception -- the migraine sufferer fully understands that what she sees is not a part of objective reality. Rather, it is frustrating in that the victim knows that her eyes are playing her false but she cannot solve that problem, and there is dread in knowing that intense pain is likely on its way.
The good news is, preventative steps can be taken when the aura is recognized for what it is; analgesics dull the pain and I have found that withdrawing from areas where there is a lot of light and loud noises will help. Getting a snack sometimes helps, too -- it seems to need both carbohydrate and protein to be effective.
The bad news is, there doesn't seem to be any discernible cause to the event; it can happen at any time and it's not always possible to medicate or alter one's behavior to cut off the oncoming event. Once the pain sets in, it can echo for days afterwards. So for you non-migraine people out there, be happy you don't get these. It's a real thing, it happens to a lot of people (even professional athletes) and it's not just a "bad headache" or an excuse to defer sex.