Hi welcome to Health care magic forum. It could be some sub clinical infection of the throat,
uvula, or teeth. When it reaches clinical level it starts to hurt .
I advise you to consult an E.N.T surgeon, for diagnosis and treatment. You may have to get the Xray, culture and sensitivity of throat swab done besides other routine tests for confermation.
Besides i advise you some diet recommendations for relief of symptoms, avoid taking ice water, ice cream, cool drinks, brinjal, and sea foods. also avoid taking spices,chillies, junk foods, and oily foods. Wishing for a quick recovery and thanks for calling.
Take more of green leafy vegetables, pulses, sprouts, milk, egg, meat, to have enough of blood, and to have general health , resistance, and stamina.Wishing for a quick recovery and thanks for calling