looks like he is about to shed. did you notice his eyes cloud up recently? Its hard to tell in the pic, but it looks like they might be cloudy now. increase your humidity to help the shed if that is the case. As far as feeding, I think a pinky is too small. looks like he can handle a mouse every 5 days. just noticed you said rat pinky, in that case, probably ok but you could maybe go a little bigger.