My Son, 10, Are Mac And Cheese Two Days Ago.

My son, 10, are Mac and cheese two days ago. When he took his first bite it burned in his mouth so he swallowed it. It was clearly visablw as he was swallowing that it was burning as it went down. I did not think much of it but over the next two days he has had a dry cough, he cries at times that his throat hurts so bad. We took him to an urgent care assuming it was strep and in all honesty, forgetting about the hot good incident. She found he did have an ear infection but noted the throat looked ok. She ordered antibiotic for the ear. 24 hours, no relief and still no complaints of the ear. When he cries about his throat he also grabs the back of his neck. I am concerned his throat, farther back and down into the esophagus is burnt. Milk seems to be the only thing he will ingest. Please help?