I think there are a couple of issues here.
Firstly, you do, in the very least, need to speak to your AME, as a medication which could potentially affect your flying has been prescribed.
The Z-drugs and term "Migraine" does seem to twitch them, (although, from previous posts, not always preclude you from flying).
The term "Migraine" is loosly used, by medics and laymen alone, I'd be a little careful about attaching a label to yourself without specialist advice.
High tech scans/examination are likely to reveal little. Diagnosis will, most likely, be made on the story of your symptoms, a "headache diary," may be useful.
Cheers, ginge.
