I don't know. But sometimes I get a similar thing. In my case it's not a terrible "pain" I get, but "horrible feelings". A constant nagging twingy ache over right eye, and sometimes slightly nauseous etc.
Now a few weeks ago I coldn't tolerate any alcohol at all. It always made the flu-ey feeling much worse. Even two teaspoonfuls! I could just about manage the 5ml of alcoholic Echinacea Angustifolia tincture I was taking.
But the last 2-3 weeks I have noticed if I feel really bad, sometimes a tiny shot of Brandy sipped very slowly will help me a lot.
Alcohol can sometimes be a medicine. Alcohol use, within careful limits, as opposed to alcohol abuse.
There's such a difference.
I remember when my old Nan was alive in the late 50s. The doctor gave her Sanatogen Tonic Wine -on prescription!