I think they would have told you if you were anemic, but you would have to know if they ran a CBC (complete blood count) in order to know what your red blood cells were at.
My feet would always turn purple and have white spots on them but I was anemic, so I figured it was that causing it. Who knows.
Oops, I meant the numbness is from sciatica (sp?). Also, I just read that poor circulation can cause changes in skin color and skin temperature, so maybe that's what's happening. I'd bring it up to your doctor next time.