\\\\I was told by my GPS a couple of years ago that I probably have arthritis in my neck (although no tests were done) so could it just be arthritis spreading down to my arms? TIA\\\
It could be, but i like the explanation given in the link by grasscarp above, although the exercises are a bit "faffy" and the bit about magnesium, nonsense. You pain certainly sounds musculoskeletal and if bad enough, a simple analgesic tablet or gel may suffice.
It could be due to wear and tear in the neck bones, but at this stage, any tests would not be helpful.