Re: could it be RLS?
It could be. I think a big thing with RLS is the need to move the limb to find relief from the sensation, and the sensation is very hard to describe. I describe it as something like an itch deep inside the muscle that can only be relieved by moving it. Still, it's not really an itch, it's just hard to describe. And it does vary in intensity from mild to maddening. What you describe could be RLS.