Hello and Welcome to ‘Ask A Doctor’ service.
I have reviewed your query and here is my advice.
Well, your explanation is pointing towards either injured mucosa in that area, that can be due to cheek bite, trauma with sharp cusps of teeth, burning with hot foods etc.
Redness increased in that area further points towards inflammation.
Do not worry as such injuries tend to heal on its own very soon.
For now you can apply Chlorohexidine gel and gently
massage the area.
Do warm saline gargles.
Avoid spicy, hard, sharp and irritant foods.
In case if there is no improvement in a week or it worsen consult an Oral Physician and get the area clinically checked..
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Honey Arora