When I was in high school, for a period of about 4 months I got migraines at the same exact time, every single day. Except on weekends. But Monday through Friday, towards the end of 1st period I'd feel it coming on, and by the time 2nd period was over, I was usually trying to figure out the best way to sneak out of class and go home.
They were so bad that all I could do to not go insane was go home, lie down on the couch with a pillow over my head and scream until I fell asleep and slept it off. I went to a doctor one time and he gave me some prescription that only worked if I took them the very instant I felt the first sign of it coming on. After a while, they stopped happening so consistently, which was nice. But then they started coming at random times and that was never fun. Fortunately it was only once ever couple months at that point.
I can't even remember the last time I had one now. I wouldn't wish a migraine on my worst enemy if I had one.