Migraine is a complex chronic neurological condition that is currently not fully understood. Several theories (some complementary, some mutually exclusive) exist.

A migraine attack has three parts:
The prodrome, the main event, and the postdrome.

Prodrome (dur. 1h-5h)
Temperature drop
Sluggishness
Dehydration
Photophobia
Echophobia
Nausea

Main event (dur. approx 20-50h)
Face, head, neck pain
Jaw, sinus, and tooth pain
Joint and muscle pain
Photophobia
Echophobia
Shaking hands due to increased andrenaline
Brain fog
Clumsiness (lack of spatial awareness, coordination)
Visual disturbances due to optical nerve impact (seeing flashes or blurry spots even when eyes are closed)

Postdrome (dur. approx 4-24h)
Nausea subsides, carb cravings
Brain fog lifts
Stiff joints
Sore muscles
Exhaustion

Please only offer advice if you are a chronic migraineur or are a researcher in the field.

For further information please consult migraine-educated physicians. More information or recent research can be found in the The Journal of Headache and Pain, the Lancet, Headache, and the Journal of Oral & Facial Pain and Headache.