I have heavy arms and legs and pressure in the back of my neck for almost 2 years?

Neurologist: I would recommend seeing a neurologist. The heaviness sensation is vague and hard to sort out sometimes but it can be what's called "functional weakness". That can occur as the result of a central nervous system problem. If your neck hurts then there may be some issue with the spinal cord at that level? No matter what, the neurologist can help sort it out.