What Causes Sensitivity In Hand?

I am a 51 year old female. Last Thursday I noticed my left had was very sensitive, to the point it hurt when lightly touched or even wearing a watch. Then it seem to move to my forearm and then to my neck. Yesterday it was in my face and today it is in my head and face. It is so sensitive it even hurt to comb my hair, much like a sunburned scalp, but it isn't. Could this be an allergic reaction to soy milk? That is the only thing I have had that I've never had before. Any ideas?
Thanks