I have a big knot on the bottom of neck more on my shoulder could this be sitting on a nerve and causing my back and neck hurt all the time?

Trigger points : A "knot" near the bottom of the neck (lower cervical spine) or in between the shoulder blade is commonly do to a muscle spasm. The descriptors provided indicates that this is likely a myofascial or muscular trigger point, which is a form of muscle spasm. "a pinched nerve" in the neck can commonly cause the described symptoms as well. Effective treatment can be started once diagnosis is confirmed.