As I understand it, it's like most things - individual, but from what I've read on a few dog lists, that does sound like a very likely explanation for her behaviour. Did she have any other vaccs at the same time? makes it easier to work out the culprit if not.

Food-wise I'd switch to real food, preferably raw and convince your husband that chemicals are harmful and dogs don't actually need them. If he goes on to Dr Jean Dodds site he'll learn a lot and no, she's not Homeopathic either, she's "scientific" and allopathic and has proved that vaccs are not necessary, I'm surprised that a vet doesn't know that. All 27 vet schools in America stated that annual vaccs are unneccessary. ( I'm assuming you're in USA from what you feed)

Hope you can help your dog.