What causes severe upper neck and shoulder pain?

Question: I had an ACDF of c6/c7 in 2011, RA for 15 years. Surgery went well, no complications, happy with results. Follow-up MRI at 1yr showed slight posterior bulge at c4/c5 with anterior osteophyte. All has been fine until this year. It seems I have had some increasing upper neck/shoulder pain begginning in XXXXXXX 2014 and peaking after a snorkeling trip in March 2014. The pain was strong enough in the neck, head, shoulder, pectoral region that I could not sleep or ride in a car without the aid of hydrocodone for a few days. I visited my primary when the pain was still present after 2 weeks. He suggested I wait to see if it improved on my own, no meds were prescribed. It seemed to settle, flares on occasion with increased activity. I had a week off of work and returned today. The pain is back again. I teach and have to write on the board quite a bit. I have upper posterior neck pain that wants to radiate over the right side of my head towards my forehead. I have dull pain or tingling on both arms from the top of my shoulder to just above my elbows. If it gets bad enough, the pain goes across my clavicle, to my jaw, ears, and on the outside of my lower leg. Since it comes and goes, I'm trying to dtermine at what point I need x-rays or a repeat MRI. I have insurance, but money is tight right now (tax day) and my co-pay is $50 for a specialist.