I've noticed that Yorkies get the shivers a lot, but with my girl, its when shes scared or cold from taking a brisk walk. If your puppy is sick and the shivers don't calm down within 30 minutes, I'd maybe keep up with the vet--if you don't feel the vet is giving you answers and you KNOW something is not right, try another vet, asap. She's a tiny little thing at just over 1 1/2 lbs, so you will definitely need to monitor her eating for a good while longer. My Lillie is over 17 weeks and I still have to keep an eye on her constantly. It may seem excessive but just think of how worth it it all is.