[Ellie May]

In my opinion, he needs to see a vet immediately or things could get worse.
They can have a bowel movement even if they are obstructed but then most likely that will stop. He can't hold food down, has inappetance and is lethargic after eating sharp bones. While it is impossible to say what the vet will want to do if anything, it is not something I'd wait out or try to treat at home.

And as Ladymom said, pancreatitis is a concern and could cause these symptoms.