Migraine for 5 days after miscarriage?

It's possible. Most of the time, migraine headaches don't last this long, but after a physical stressor like a miscarriage, it is possible to have a long headache like this. Make sure you stay hydrated, and if the headache persists, see your physician. Hope you feel better soon.
It can happen. First let me say I sorry I am for your loss. Yes a persistent headache after a major stressor is possible.