I would get him to an emergency vet if possible, try calling your regular vet's number and see if they have any emergency vet info.
In the meantime, you can mash up his pellets (and maybe some carrots or something similar) with water and syringe feed him some food. If you have access to Critical Care (they might sell at your pet store, it depends on your area), that would be a good thing to use right now.
Good luck. Is he eating hay?
We have critical care and a couple of hours ago, we gave him a teaspoon of feeding. Do you know how much we are supposed to give him. He isn't really having many bowel movements and when he does they are really smell. We are thinking he might be constipated.