First off I would be safe and take the snake to a vet, you don't want to treat it for an RI and that not be the problem... If your snake does have an RI they are VERY hard to treat without antibiotics. They will probably give you prefilled syringes to give shots once a day. Also talk to the vet about your set up. For me I have mine on cypress mulch (forest floor). I spray the tank once a day (in the morning). The aspen bedding could be too dry.
GOOD LUCK!!