Thank you for choosing HCM.
As your mentioned, your son has had a stuffy nose along with flushing
around his cheeks and around the nose alongwith fever
He probably is developing infection of the subcutaneous tissue
of his cheeks and also seems to have sinusitis
I suggest you should take him to his doctor soon to have him examined, since this may continue to spread, he will probably be started on antibiotics.
Hope this helps.