Just a quick question, has anyone experienced their dog having a reaction to a shot?

Kipling got his 3 round of puppy shots and a bordetella booster on Tuesday. Just yesterday I noticed he had a small lump behind his right shoulder where they gave him one of his shots. It is about the size of a nickel or quarter. It doesnt appear to be sore or red. Other than the bump there are no other symptoms.

We asked the vet tech today about it and she said to wait until Monday to see if it goes away.

I guess I am just paranoid