is he going to the bathroom regularly? this is important. if he is not eating it could be his back teeth are jagged and growing wrong, or it could be an intestinal problem, which can be very common and very fatal if a rabbit's diet isn't just right. my rabbit has experenced both of these problems and she is only a year. first it was her teeth, then her diet. she is doing very well now, but needed veterinary care and medicines. I did have to rush her to an emergency vet, and i would really
try and do this if possible for you to find an emergency vet that sees rabbits. For now - i would give him lots of hay. that will be very important for him.
i hope he is doing alright today- and i wish you the nest of luck in finding a vet asap.