My two cents;
I don't believe you have to go so far down the road to critical mass (when alcohol and drinking become a destructive, obvious issue) in order to say or know 'there is a problem here.'
If you're feeling disturbing physical effects after a night of drinking, then it is time to change something. What you're describing is concerning to you, and does not seem quite right. Maybe your bodies natural tolerance is trying to nudge you, make you aware it does not like having to process that level of alcohol.
It's good you've seen your physician, wouldn't be a bad idea to schedule a full physical just to make sure the motors running right. Cutting back is probably a wise decision.
Good luck to you, and welcome to the forums.