What Causes Pain And Stiffness On The Left Side Of Neck?

I have been having for the past week severe throbbing in left side of neck with sever stiffness. My skin there is also tender to touch and feels almost sunburned. at the base of my skull is very tender and when touched you can feel a sensation go to either side of it. Xrays were done but my spine looked straight and in line. I am 45 years old. Could I have an arthritis of some sort. the severe throbbing in the neck has subsided but still have stiffness with a dull throb behind left ear and head.