I am 22 months out from completeing radiation treatment.

Three weeks ago my lower left jaw felt sore as if someone had punched me, and I noticed there was some swelling at the jawline. I saw my primary care doctor, and he said my lymph nodes along my jaw were swollen and I must have an infection somewhere. I was not sick, and I didn't have a sore tooth. He prescribed 10 days of penicillin, and didn't seem concerned.

The pain and swelling are gone now, but I can't help but wonder if this could possibly be the signs of something more serious. I have a history of being misdiagnosed.

Any input appreciated, thanks!