Eric,
Definately monitor the area. I had a sore area near my tomgue, back by the molars that the radiation oncologist couldn't see/said was nothing. My surgeon finally biopsied the area last week. I go in for surgery again, today.

Probably not the same as the neck pain, but I believe that we know our body best, expecially after two bouts. By the way it was an area that was radiated. You can't give this disease a breather! Good luck!