I'm sending good vibes for Max. I really hate to say this, but the symptoms you're describing sound very much like our last dog's, whose kidneys failed at 13. We had him pts, but our vet told us he wouldn't have survived another 24 hours. He gave me a look that just said, "Mommy, make it end. I can't take any more." I really hope that things aren't that far along with Max, but you might have to prepare yourself for the worst.