Last night I was rubbing Finnigan's neck and noticed a lump on the side of his neck under his jaw. It is under the skin and is maybe the size of a quarter at the most. Finn is only 17 weeks old so I don't know how serious it could be. I'm going to take him to the vet and see what we can find out but I was curious if anyone has an idea what it could be. I was hoping to avoid a trip to the vet because I know how quickly the cost can add up but I worry too much to leave it for a few days and see what happens. Hopefully it will turn out to be nothing.