Brief Answer:
Canker sore in mouth seen.

Detailed Answer:
Hello dear, welcome to Ask a doctor's service.
I read your query and here is my advice.
I have seen the two pictures you attached and the throat is red and a canker sore is seen. It may have been caused by any mouth wash products, toothpaste, or a minor injury, or any food such chocolate, strawberry or nuts.
I think you can let it and it will go by itself in a week . There is not need to take any treatment just avoid food that can irritate it.
If it doesn't seem to go you can use hydrogen peroxide or benzocaine mouthwash found over the counter in pharmacy.


Hope I have answered the question.
Let me know if I can assist you further.

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