Welcome to YT!
I am in Annapolis, so not too far from DC. I'm glad to see a daddy of a Yorkie on here, there's a few on this site, but not enough.
Nice to meet you!
Most Yorkie breeders will keep the pups with their moms until 12 weeks old or older. 8-12 weeks is when they learn about bite inhibition so now you have the job of teaching your pup! Another older dog will also teach a young pup about it too by yelping. That's one thing you can do (as silly as it sounds) when the pup bites you too hard, you have to yelp in a high pitched voice, to startle them. That's what their mama dog would do! Or you could replace your finger with a toy or a chew bone, etc and show her what is okay to chew on.
But don't worry, biting is a very normal behavior in puppies especially as young as 8 weeks, so it will get better! Just keep up with the training