I had a yorkie and a cat and they loved playing together. It's sounds like to me just normal puppy behavior. In time, they will begin to calm down especially as the puppy gets older. I don't think it's aggression at all. In fact that's how my 3 yr old play with our cat. They had these spurts of spontaneous playing and they would fall aspleep together. This went on all day like clock work. I was worried at first until I notice the ca'ts behavior. She was the one starting the play fighting!
She would run up to Dutch, take a few swats at her (claws in) and then take off running. Of course this would instantly set Dutch off and the play fighting would begin. When I saw that, I knew the cat was okay.
As long as your cat has an a place to escape too, it should be fine. Cats have a way of letting puppy's know play time is over.