My hands are often grayish or purple because of my pots, but today both of my arms are gray?? i have a bad headache, not sure if the 2 are related...

Headaches are common: ...in patients with POTS, but it's common in the general population as well, so it's hard to say if POTS is the cause. Purplish discoloration of the legs is common in POTS, but not usually in the hands or arms. That's more likely a symptom of Raynaud's phenomenon. If you're on medication for POTS, that can further confuse cause & effect. You should consult your treating physician about this.