Your puppy may be shaking due to stress, anxiety, pain, hypothermia, or hypoglycemia. If the shaking continues for more than 30 minutes or any new signs develop have the puppy examined by a veterinarian. Make sure the puppy is not cold and attempt to warm it with blankets. Feed the puppy canned dog food or sugar water/Karo syrup to make sure it is not hypoglycemia.
Your dog is either cold, frightened or sick. Yorkies are very small, usually with short hair, and rather delicate. If his/her nose or eyes are runny, he/she is obviously ill and should be seen by veterinarian quickly.
If he/she is new to you, it may be just nerves that can be overcome with TLC. If he/she is in a cold environment, get him/her a coat. Holding and snuggling works wonders
I have a new yorkie pup he is 8 weeks old and I have had him 4 days he threw up some today and he sleeps a lot do I need to worry he weighs 1.5 lbs