I'm worried about what this may be. The entire bottom inside of my left cheek is red and slightly raised. It is flat and smooth with no pain. I noticed it after I ate ketchup/mustard...I could feel the acid, and it swelled up. I'm not sure if it was this way before the food. It has been this way for at least a week. Should I see a dentist or dermatologist??

You should see you dentist