Start by reading the sticky at
https://www.askmehelpdesk.com/dogs/i...tml#post251802
Read through the paper work and see when he had his DLCPP or whatever shot. Call a vet and set up an appointment. Usually they will want to give the puppy another combination shot 2-3 weeks after the first one. I am not a professional, but your vet is.
RubyPitbull isn't either. She has never said much about how she has come know so much about dogs, but it is clear from her posts she knows far more than your average dog owner. Many dog owners don't have any idea how little they they know. I certainly was much lower on the learning curve before my family began our work with dog guides. We have mentored by the best. We have a constant stream of new people here, and I may develop conficence in some others. Don't let titles or green boxes fool you.
In some of the other forums in Home and Garden, we have some fine professionals that give great advice. Unfortunately, in the almost 8 years I have been answering dog questions on the net, I have been very disappointed with the advice from those claiming to be professionals. There is no national building code for dogs and few apprenticeships. Some of the best people I have seen, like Ruby, are those doing rescue work.