The Solo Stone: Jon's Skin is Supposed to be Green?

Jon looked at himself in his mirror and saw that while he was dressed and looked well-showered, there was something definitely wrong, because normally he had green skin! *Everyone* had green skin. It was so freakish to see himself with pinkish skin. How could he let people see him like this? They'd call him a freak right on the spot. *Maybe I could wish to have my green skin back,* Jon thought to himself. But why did his skin change color in the first place?