What Causes Swelling Of Forehead And Eye Along With Vomiting?

My 15-year-old son has been very ill since Sunday night...he had red swollen eyes and a fever Sunday night, vomited early Monday morning, and hasn t been able to eat anything and has been lethargic and achy since. His forehead also swelled up yesterday. We took him to the doctor who said he has a bad cold, possibly mono. The instant test was negative for mono, but we re waiting for the other blood test results. The dr. said the swollen forehead could be a symptom of mono, but I can t find that anywhere on the internet. Is this true, or could it be something else?