J.M.
J.,
One possibility is, he could have allergies. The weather has been changing and my doctor said that many people of all ages have developed allergies that they haven't had before, including me. I have had cold symptoms for over a month. My doc said that there is a bug going around, too. My son (16 yrs) has also been sick for going on 3 wks. I would just be patient. Have you taken him to his ped?