What Is Causing The Itching And Colour Change Of My Palm While Exercising?

Hi. I am 40 and healthy. I am recovering nicely from wrist surgery- 5 weeks ago- due to trauma. I shattered the wrist and broke the radius. A plate and claw were installed in my forearm and connect to my hand. I am gaining movement back, the pain is manageable without medication and I started p.t. a week ago. Everything is going very well, but for the last week or so have been experiencing extreme itching - not just the scar site, but especially on the palm of my hand. The palm also turns a purplish red color when I am using it or doing the exercises - not sure if that is related at all or not. I am not taking any medication for it and will see my surgeon at the end of next week for a follow up. Just would like an idea of what it is and how to make it stop.