Yes, it's migraine - migraine comes in many shapes and guises.
I suffered for years, and my GP explained to me that you can suffer any or all of the phases - the aura (lights), the pain, the vomiting, the aftermath when you feel you have been hit by a bus.
I used to take Propain Plus for mine, it worked, but he needs to sleep it off if at all possible, I've suffered for up to three days sometimes before it went completely - I would feel completely washed out for about three days afterwards.
The pain is agonising and only keeping still, taking strong painkillers, drinking water, and sleeping used to send it away for me.
I wouldn't expect anything of him for the rest of the day....