Somethings wrongs wrong with my 7 year-old ball python. He is for lack of a better description very, lethargic. When I left for work this morning he seemed to be fine but when this evening when I came home he was/still is laying approximately a 1/4 the way out of his hide box located on the cool side of the terrarium. His only movement at all was minimal when I moved a branch that he was partially touching. His skin seems sorta dull. This is so not like him but I can't figure out what's wrong or what to do.

I though maybe something had gone wrong with the temperature but when I checked the min/max on the most centrally located thermometer (1 of the 3 that is slightly on the cooler side of center & about 6'' from the bottom) was 79.9 F / 86.9 F. He has a hide box on both sides & is comfortable with either. He has a larger water bowl (cool end) with fresh water daily. The humidity as be 39% to 51% the last several days. He last ate last Thursday.

Please, any ideas or suggestions would be appreciated! I have never ever seen him like this. To be honest for a moment I was afraid he had died...