if he is not coughing then it is probably not kennel cough. kennel cough is a coarse, dry, hacking cough,it sounds almost as if the dog needs to clear his throat. extra exercise and activity would make it more noticeable.maybe upper respiratory like Andrea said.good luck at the vet, hope it is nothing serious. let us know what happens!
Yes most rep breeders require a Vet visit within 72 hours of taking possesion of the pup. I would also on your vet visit bring in a stool sample as well. This just rules out any parasites that can cause problems later on.
Hope he is feeling better and does good at the vet!!