Do you know what shots Baxter got? Did he get lepto? It's the "L" in a combo shot.
If he got the lepto vaccine today, I'd call the ER clinic now and explain the situation. We had a puppy here just today have a similar reaction (vomiting) to the lepto in his shot. She had to rush him back to the vet who gave him a shot of steriods and another one of Benadryl.
Here's the thread:
http://www.yorkietalk.com/forums/gen...ml#post2393856