The commonest STD which can occur in the mouth is a herpes infection. In this infection, the main symptoms are blisters which appear on the lips on the gums - these blisters acan be easily seen.
Other STDs like gonorrhea
etc which can also occur in the mouth also cause formation of ulcers or sores in the mouth , usually in the inner cheesks, lips or gums.
Since you only have a pain deep inside the mouth and have no blisters or sores, it is likely that what you have is an infection which is not an STD.
The infection could be due at the tonsils or pharynx - the deeper part of the throat.
Please take the following steps at home and see if they help:
- Take Ibuprofen, 200mg thrice daily after food.
- Gargle with warm saline water twice daily.
- Rinse your mouth with Chlorhexidene mouth wash (available OTC).
If the pain persists after another 3 days, please consult your doctor. You will need a throat swab for a culture and sensitvity test.
I hope this helps.
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