About a week ago, I started to noticed a bump, kinda horizontal circle thingy on the back on my in the bottom left gum. it is extremely painful and won't go away. I have a strange thing that gives me canker sores often (confirmed by Doctor) ,could that be part of it. I haven't gotton a canker sore on my gum before and it doesn't feel like one. Also I have a ringworm but u don't think ringworm a head in your mouth. Please reply I don't know what it is