if your dog has a febile fever and is already on antibiotics i would not do to much other than let it get some rest and plenty of water while its recovering lots of pets and love
Call your vet's office and talk to the receptionist. Tell her your dogs symptoms and ask if you should bring him in. If they say no but his fever persists bring him in anyway.
Take your dog to the vet and see what the problem is. You should not ask people on the internet what is wrong with your dog when the only person that can really give you good advice is a vet.