Child Having Enlarged Tonsil. Relief With Antibiotics, Red Patch On Side Of Tongue. Condition Related?

Hi, My 4 year old has one enlarged tonsil . It was sore in the beginning, he took antibiotics which finished a couple of weeks ago. Pain is gone, but he says the underside of his tongue / back of his bottom front teeth hurt when he eats (I can t see anything to cause that pain). The tonsil is still enlarged almost to half way across his throat. I noticed tonight too that he has a 6-7mm long, 2-3mm wide red patch on the top left hand side of his tongue, the surface of the spot looks smoother than that of his tongue. Could these things be related? He says his throat isn t sore but I still find him to be crankier than he normally would be.