I have found a bump on the side of my Westie's face. It almost looks like a pimple with something inside. The area is not discolored nor has any hair fallen out. Last year he was attacked by a pit bull. As a result of that he had to be shaved and the puncture wounds "glued" closed. Could this have been another wound that we missed? Any advice would be appreciated. He goes to the vet at the end of the month for his yearly check-up, but I'm really concerned. Thanks.