Two days ago, after I brush my teeth, I noticed that my gums on the upper right side started bleeding. Yesterday, it was very inflamed and painful to brush and touch. It's now reddish in color.
I’ve just been to the dentist about a month ago for my twice-a-year routine dental check up and she did not mention anything about me developing gingivitis. Can gingivitis or periodontal disease develop in just a month? It’s only on the gum on the upper right side of my mouth. Does anyone have any ideas? I would be grateful for any information.

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