Feels like a quick zap under the skin that itches last for just a second.. Appears in all places on body. Have bumps on back of scalp (do not itch) but get a scab on them and they also come and go. Have been checked for Vit. B-12 & D. but those are alright. Been using Selsun Blue shampoo for 2 weeks ---bumps still occurring. Hands fall alseep (my best way to expalin) while driving or chopping food....sometimes wake up with hands alseep. The tingling -itching is so upsetting to me...When I get them no matter where I am I say "Ouch" they are just so sharp and when I rub them they go from that area. It does not happen everyday but it is happening more often and scareingme. Any ideas?