Hi I went for a routine dental cleaning I have every six months. After my gums were sore to brush near a bottom tooth and above gums. The tag that joins my gum line to lip line sore as if cut.This went on for two weeks when I developed a canker sore below tooth where it was sore. In an area not common for cold sores. Not for me ever. Also sore gums above and swollen gums on top of canine tooth. Hard to brush. Nothing is going away. Three weeks later! Still have canker sore.