Well, he is a cutie patootie. He definitely has a lot of yorkie in him - that's for sure. The first thing I noticed was the length of his nose, though. I think he's probably mixed with something.
But who cares right? He looks like he is just a love bug!!
Have you taken him to the vet yet? You should do that as soon as you can with him being so young. Perhaps get the vet's opinion also.
How much does Jax weigh? A small/toy breed dog is still really vulnerable at only 8 weeks old, so study up on the signs of hypoglycemia and keep some nutrical on hand ok? Also, if he isn't done with all of his shots, be sure to keep him away from other dogs right now.
Welcome to the forum! Very nice to meet you and Jax!!