Your C4 nerve is part of the Phrenic nerve (C3,C4,C5)- important for controlling your diaphragm and thoracic muscles for breathing. C3,C4, C5 can have pain, pins and needle sensation from the shoulders, in side of arms and even pinkie and ring finger loss of sensation.
I had a sublucsation (spelling) of my C4/C5 and fusion due to it in 2001 and my symptoms was pins and needles and loss of sensation shoulders,arms and especially fingers pinkie and ring fingers both sides.
I cannot comment on any of your other symptoms but would suggest that you find a Dr that can give you all the positive and negative impact on surgery and delaying it.
This is almost exactly what I am going through right now. Only I started with c5/6, then moved onto 4/5. Now, they are noting problems with 3/4. My right hand is totally weak and my shoulder down to my fingers feel achy and just plain hurts. Am going to the neurosurgeon on Tuesday.
TNF alfa inhibitors: remicade, embrel, humira. orencia They work like a charm. Get off sugar and starch in the mean time.
Blessings