Could be:-

Allergy, though food would also contact your tong and mouth, those would also be red. Is your tong dimpled around the edges. Puffed up cheeks. Tired?

Yeast. Could be, though to find out you need to get your doc to prescribe meds for Thrush, usually nystatin suspension. Tasks bad unless it's got flavoring in it, a couple of gargles of this and you'll know. But then you should ask the question, why do I have a yeast infection in my throat. Have U been taking antibiotics for a long time? Don't use systemic meds for this, they'll damage your liver.

Have U been taking large amounts of Vitamin C over a long time and have stopped suddenly?

Vomiting allot? Trying to control your weight by voiding?

Eating something that is caustic or irritating? Coffee, Coke? Acidic wine? Caustic vits or minerals, especially if taken using a blender?

Is there any pain? Swelling? Stomach swelling/ sticking out?

Healing crisis? Is there something you're doing to heal?

Are you a sword swallower? (Just joking)

Allot of possibilities based on your explanation of your symptoms, however, I don't think it's like threatening.