Hi Ann!
Photophobia is a sign of the "headache phase", but for a proper dignosis, he would have to see a doctor.
There are stages within a migraine attack: see Anatomy of a Migraine for more info on the migraine process. It is possible he is having Silent Migraines, but again, he would have to go to a doctor for a proper diagnosis.
Also, maybe having an eye exam if he has not had one in a while would be a good idea as well.
Good Luck!