Brief Answer:
Gingivitis

Detailed Answer:
Hi.
First of all thanks for approaching us for your query.
I read through your query.

I saw the pic also (which was not that clear). I must say that there is nothing to worry in this case. It can be a gum inflammation(gingivitis). It can be reduced by applying metrogyl gel. Please do nice salt water gargle as many times as possible. Also do chlorhex mouthrinse (concentrate more on that area). Do till 30th (as you have dds appointment). It will be reduced by then. If still it is present you can meet your dentist and get it treated as clinical situation will be better diagnosed. It is not related to cancer. Please take it out of your mind. Cancer is one such disease that if you keep thinking of it last it will come. So please don't think about it (psychological cause). So be calm and keep positive mind. Happy and calm mind can be best medicine for any disease.

Hope you understood what I meant.
Have a happy and healthy day.
Thank you

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