We have a 3 month old puppy. He had never been given any vaccinations. Since we got him we have fed him only raw chicken (from leg quarters). About a month ago he got parvo. We took him to the (non-holistic) vet Friday evening, and let them do their normal treatment. He was fine by Monday, and we took him home. The vet recommended that he eat special vet food until he was recovered (3 or four 15oz cans) and set up an appointment for a booster shot in three weeks. We used up the canned food, and returned him to his normal diet. He was completely better.
Last Thursday he got his booster shot. The next day he was laying around, but otherwise OK, he was eating fine, just a little lazy. Saturday he started making hacking sounds like he was dry heaving and has done it ever since. His appetite is still fine. We haven't taken him back to the vet because we don't have transportation, but I was unhappy with the sort of responses I got on the phone from the vet anyway (they think maybe giving benadryl would help). I don't trust them. I fear this is some kind of reaction to the vaccine, but of course they don't think so.
What might be wrong with him, and what can I do about it?