Again with my Migraines?

I get migranes really really bad, all of the time. And Im fine! That's what was so irritating...They put me on Elavil...it's an antidepressant, but it seems to be getting rid of my headache... I guess something in the antidepressant is curing my headaches. (Lol, Im not depressed tho as a side note! Never was!)