I did give Benadryl this last time and he didn't seem to be quite as sore but he still just was not himself.
Like the OPer he was fine until about 3 AM and that is when he let out a yelp when I picked him up to move him while he was sleeping on top of me.
When I called to see about pain meds they suggested the baby aspirin and after just one dose he was much better. Next time he gone for shots I'm going to ask while I am there for a pain med so I am not fool around with him being in pain again. This was only his second time getting his rabies, I thought I was being prepared with the Benadryl dose prior to the shot but it was not enough.