This does not sound like a life threatening type reaction, especially if they felt they could give her a med to take home. I personally would give the Rimadyl. It would help her with the discomfort she is having. But...that's just me.
As for vaccines...they are very important especially in young dogs. My vet follows the AAHA recommendations.
https://www.aahanet.org/Library/CanineVaccine.aspx
While you think your dog is not susceptible she is .. just taking her to a pet store..or heck, even to a vet is risky for a dog not vaccinated. You have no way of knowing what other people are doing with their pups.
Good luck with your decisions for your pups.