Cheryl,
Make sure you gently floss between your teeth in that area, even more than once a day. I have a little area that seems to have gotten irritated, and I found that flossing more than once at least until it is stabilized takes care of it.
I know what you mean about the fluoride being irritating, but I think it more likely you have what I have experienced. Especially if you have dental work there--actually my one crown is in that area for me--make sure you get it cleaned out more than once a day for a time (again, don't make it bleed, but if it does spontaneously bleed, that ain't bad at first, just means you cleaned out the inflammation and bacteria) Of course see the dentist if it does not resolve, and especially if it gets any worse than what you describe.
Anne