hi, thank you for your query, your sons age and symptoms point towards strep throat. The common symptoms of strep throat are- 1.Difficulty swallowing 2.Red and swollen tonsils, sometimes with white patches or streaks of pus 3.Tiny red spots on the soft or hard palate — the area at the back of the roof of the mouth 4.Swollen, tender lymph glands (nodes) in your neck 5.Fever 6.Headache 7.Stomachache and sometimes vomiting, especially in younger children 8.Fatigue apart from it,other causes can be viral outbreak(chicken pox),cold sores,or just irritated minor salivary glands i would advise you to see your dentist once for confirmation thank you, wishing you good health