Need help with crested gecko

[Zik]

Hi, I am new to the forum and need some help here. We've got a Crested Gecko about a year ego. He’s been doing fine until about 5 days ago. I’ve noticed that he is not active, basically doesn’t move at all. His skin looks normal and I don’t see any signs of distress. Yet I don’t think he is pooping much ( or at all?) and 3 night ago I fed him his favorite mealworm with calcium and he didn’t eat a single one. I spoon-fed him some banana the next night and tonight I spoon-fed him banana mixed with Repashy Superfood that he normally eats. He ate about a 1/2 -2/3 of the tea spoon. I also haven’t seen him shad for at list 2 month now. Today he looked kind of week, one of his legs was hanging down and it looked like he was going to slide down. When I handled him he was running up my arm as he’d normally wood. What do you think is going on?