Hi there and welcome to Just answer!! I am Dr. Loretta, a licensed veterinarian and I am happy to answer your question.
there are 2 possibilities for this cough. This is the first sign of Congestive Heart failure and considering your guys age, this is a possibility. This could also be the start of Tracheobronchitis. This is a contagious disease that is often caught at a kennel, groomers, vets office or dog park. If this is the problem, this is a self limiting disease that will eventually go away on its own but he will require medication from your vet.
If your guy is still eating well and is now out of this episode , then there is nothing else you can do but to calm him down. If this continues, have your vet examine him Monday to know for sure.
Good Luck! Sincerely, XXXXX XXXXX