Wonderful...so I gave you the name of a vet who gives rabies and DHPP at the same time.
For future reference, that is not recommended by the AAHA. For years it was done, but now it is suggested that those vaccines be given at least 3 weeks apart.
I personally like Convenia. It does away with worrying about giving meds on time! Did he have some sort of skin infection perhaps from the scratching?