Hi MHewitt

I am a Neuromuscular Thrapist,From What you describe in your post. I would say you have Trigger points in your Scalenes muscles(located on the side of your neck) which will refer a nervy type pain to your deltoids and many more muscles down the Arm and into the pecs.
Other Muscles with Trigger points that will refer pain into the Deltioid(Infraspinatus, Supraspinatus, Lats, Teres Minor and Major,Pecs).But i would say the Scalenes will be your main problem(Constant chest beathing, ie Not breathing from your Diaphragm will cause the scalenes to be over worked which will create Trigger Points).
Please do not follow the surgery advice as this problem is certainly treatable.
Get yourself to a Manual or Soft Tissue Therapist(i think they are called Licesned Massage Therapists in the USA,likely to be the same in Canada).
Do yourself a favour and get a book called "The Trigger Point Therapy Workbook by Clair Davis" it explains how to self treat trigger points.Best book i have ever bought.
Dont Give Up
Danny