He was born in November 2017 that makes him only 6 months old.
A dog is a puppy up until 1 and a half years of age!
Have you seen a Chiwawa puppy against a Great Dane puppy? The One is much bigger than the other one, but its doesn't make the one dog a puppy and the other one not if they are both the same age!
Fair enough, I have known plenty of puppies that can run quite well at 6 months old, especially if they have other dogs and puppies to run with.
The only puppy that I have seen that couldn't run very well at 6 months was a Saint Bernard, mostly because it was shy, and awkward around people. (owner kept it inside too much)
Glad your pup enjoys running!