My 14 year old son started with a sore throat and stuffy nose for two days. Now it is hard for him to swallow , and he has pain in his chest, head aches, (still a stuffy nose), and tenderness in his neck . He swims, and when he does a flip turn, he says there is pressure in his head. He doesn t have a fever. Does he need to go to the doctor, or is this a viral infection?