My first thoughts are Candida.
Do you have a coating or white areas on the tongue?
When I get minor mouth irritations, I swish with Oragel peroxide.
http://www.theonlinedrugstore.com/Or...-p/1673888.htm
Colgate makes one too, but I don't recall its name.
This foams up and kills any germs that are taking up residence in your mouth or gums.
This typically stops any mouth irritations before they get worse.
Since you are having sinus drainage and using antibiotics, I think this is the most likely cause.
If you are developing thrush, I'd get a doctor to give you nystatin, to treat it.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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