Migraine Headaches

What is a Migraine Headache they say it is a neurological syndrome that is characterized by changing perceptions of the body, severe headaches, and nausea. Physiologically, the migraine headache is a neurological condition. And from what I understand is that it is more prevalent in women than men. I can attest to this today. My head hurt so bad this morning that I went to work for about 1 hour and had to come home. I took my Tylenol and fell asleep for about 2 hours. When I woke up the headache was pretty much gone. The crazy thing is that I can't even remember going to work. I don't think that I've had a headache near as bad as this one before. Could it be that Migraine headaches are related somehow to sinus infections? or maybe even STRESS?