I am really hoping others here may have had similar experiences and can reassure me. My whole life I've had a sensitive mouth, with breakouts from foods/minor trauma etc. About mid-April, I noticed a small sore (white, kind of rough to my tongue, not terribly sore) at the base of my left lower canine tooth. Went to dentist when it didn't heal after 3 weeks. He scheduled a biopsy for 2 weeks later and in the meantime, told me to use hydrogen peroxide on the lesion. I did that and the area completely healed- there was nothing to biopsy, no roughness, no redness, nothing. About a week later, I developed an ulcer in the same spot. This time, we biopsied right away (awaiting results). In the meantime (2 days later), it looks like I am developing another ulcer at the base of an adjacent tooth. This is freaking me out completely. What could cause this? I don't have any lymph nodes or sore throat.