I recently came into the possession of a year old pastel ball python (Pythagoras). He has been a fairly social always moving around kind of explorer of a snake, on his last feeding (friday april 25th) he feed as normal except when he had most of the mouse down he extended about 1/3 / 1/4 of his body vertical and finished consuming the mouse (tail end). Is this normal or a sign of something wrong? Since then he has been in his hot side hide and not coming out as far as i know. I looked him over today to see if he was just starting the molting process; It does not appear so to me. His scales seem to be a bit "duller" than usual, I have not seen any pinkish hue of the underbelly, the eyes seem to be slightly "fogged over" looking. If this is the start of the molting process around how long does it seem to take overall? And should I change anything about his enclosure? his vivarium is 2ft x2.5ft with a heating tape on the underneath on one side with a hide and a water dish over the heat mat, cold side has a water dish and a hide as well (rarely uses the cold hide). I keep the humidity between 60-70% as best i can with work and all. The temp inside seems to stay between 72-78F. I have a couple chunks of treated wood from my local pet store for him to climb around and rub on.

any advice/ input would be much appreciated

Its a post it note for a size/scale refrence.