I have a spitz pomerian whose 16 years old since the last 2 months he's having a deep wound and I think that is maggot! I took him to the vet little late :( over there he was given 4 injections and prescribed turpentine oil now after applying turpentine oil the dog is screaming and crying it raises its back while it walks!This was the first dose is this natural?He has the wound at the side near his tail!

Sounds like a warble. They sometimes have to be surgically removed.

It's not normal for any medication to cause severe pain. I'd go back to the vet and have them treat your dog a little better.