My puppy got her second booster shot last night. She did not sleep well at all and today is acting not her normal self. She is very lethargic and sleepy. Is this normal? There is no swelling or loss of appetite, just being very sluggish.

It is probably just the after effects of the shot--the puppy's body is working to respond to the vaccine. (Call your vet and double-check! He needs to know if she is feeling bad.) If this is all it is, she should be back to normal by tomorrow.