I have a knot(grape size) on the back of my neck (under skin between muscles) , it moves right to left as i turn my neck, tender to push on, any idea?

Normal lymph node: We have lymph nodes scattered throughout our body ; they are often detected in the neck where they sit on top of neck muscles. These nodes are little fluid strainers that take body lymph ; remove stray germs from things like bug bites. They are often pea sized at rest ; grow to dime sized when working. Within 2-3 wks they often shrink back down unless they are stimulated further.Ur doc can confirm.