Update--
When I went to change the bed, there were a couple of BIG wet spots on the bed....and he has been going down to his litterbox.
At present, he's ticked at me because I closed the bedroom door. Trying to let the mattress dry out after cleaning it and spraying with Febreeze (which I REALLY hope works!)
And he's still following me around like a little puppy dog and his ears and nose aren't quite so hot as they were earlier...