Hey man I hear ya, they think if you come into the ER with a massive migraine as I have done like you have done, they automatically think your a drug seeker.
They do what they can and kick you out the door telling you to go see a specialist.
I went and finally starting seeing a pain specialist and he gave me pain meds but that was just a cover up thing, then once I did get off the pain meds I was on for about a year I had really bad rebound headaches.
I finally found a specialist in migraine headaches and did Botox and man they have been awesome for me, Ive done 1 round of shots and feel so much better, no meds, and feeling better everyday.
here is the guy I go to and he is awesome!