I believe Webster lists stubborn as the first definition for Yorkies
WOW, you have done well with training so far for only having her a short period of time. I have to say my favorite command is "leave it". I never used it before our training class this past summer but I have since found it to be the best word in the world!!!
Congrats on your new baby girl and good luck with the potty training. It just takes persistence and NEVER EVER EVER letting her out of your site while loose in the house. Hopefully someone will paste the link on potty training for you as I don't know how to do that but it has wonderful information!