Mel, I had virtually the same feeling a couple days back, but mine was only over my feet.
I could have swore there were a couple of ants crawling over my feet, but when i look down at my feet, there are NO ants or anything else anywhere, this hasn't ever happened before, it only happened a few times over a couple of days and has now stopped [ i hope] altogether, i am hoping its just a sign of the nerves still trying to repair themselves, because i have noticed in the last couple of months, the numb parts are getting some more feeling back in them.