8 month old ridge back 3 weeks ago started being tired and is hobbling?

ermm...not tonsillitis to be sure. the tonsils are in the throat not in the legs and I don't even know if dogs have them. Maybe panosteitis? Give him a children's aspirin and a vitamin C twice a day with his food. Keep exercise to a minimum and he will grow out of it. If the pain becomes too bad ask the vet for some rimadyl.