Gulliver had a bump on his bottom lip, right under one of his canine teeth. It looks like a skin colored bump with some black in it, I would say it looks like a blackhead but I don't see where it would pop, the black looks way under the skin. The bump is a bit bigger than the tip of a pen. Do you think its acne? Will it go away? It's been a couple days now and I'm not sure if I should take him to the vet, it does not bother him at all.