Poor baby. Puppy shots sometimes makes them act like your human babies after they get their shot. sometimes they get sick, fever and such. he probably is sore from the shot too. Did he move when they gave him the shot? so types of shots hurt more than others. give him some nutracal if you have it.
When any of mine dont want to drink, I dip my finger in water and put it to their mouth. They usually will lick it off. If not open his mouth and make him take a drop or two. He should be feeling better tomorrow. I hope so. I will be watching for an update. Give him grandma kisses for me.