Sabrina,
It sounds very similar to the tingling sensation I get when I tuck my chin down towards my chest, or sometimes just when I look down. It varies in intensity, and doesn't always happen, but when it does!!! Sometimes it just causes a tingling sensation in my hands, but every once in a while it will feel like I've grabbed hold of an electric cord, shocks all the way to my butt and down the back of my legs
There's a name for it, I believe it's called L'Hermite's Syndrome. My radiation oncologist says it's "normal" and should clear up in time.

Good Health

Chuck