I can't answer to the blue hands, but have you ever seen a chiropractor for your tingling hands/feet? I'm a pianist and had problems with tingling and numb hands in high school. Every doctor we visited couldn't figure out what was wrong and eventually all came to the conclusion that I needed to stop playing piano so much. Finally, my mom decided to try a chiropactor. Five mminutes into the first visit, he diagnosed me with a pinched nerve in my spine and fixed it immediately. I've never had problems since, 13 years llater.
Lol septmomma and I were in the same brain wave lol
There's a condition called Raynaud's Syndrome. It causes blue, tingly hands. it's most seen in women not sure if it affects feet also though. I saw it a couple times when I worked as a patient care tech in a hospital (they didn't come in because the raynaud's though, it was just part of their history). You can look up Raynauds on wikipedia, but remember always use your doctor for a final diagnosis.
Is probably what its called raynauds phenomenon. Its a common thing caused by impaired circulation and can be brought on by stress, and cold. Nothing to worry about, just take extra precaution with cold. Can be exacerbated by pregnancy as well.