Diagnosed with pinched nerve in should that affects left side of body and neck. 1. Get help from a doctor now ›. Depends: pinched nerves in the neck my affect the arm on the side of the nerve root compression. Symptoms may include shooting pain from the neck to the arm, forearm and/or hand.inched nerve: Each nerve in the back supplies only one part of the body with feeling and motor control. See this link for more explantation: http://www.Nlm.Nih.Gov/medlineplus/ency/article/000442.Htm the shorter answer is no; a pinched nerve will not affect the whole side of the body.