I developed that exact hand appearance after getting ME/CFS. It varies from day to day though. I suspect it might be due to some blood vessel dilation malfunction.
It may be the microvascular arteriovenous shunts that dilate (like in erythromelalgia, which goes with both hyperhemia and tissue hypoxia).
Did you notice if your red hands/feet symptoms are more proeminent in summer than in winter?
Did you notice the hand redness increases when you bent over with your hands down to the floor and then your hands turn pale when you stand and raise them to the sky?