Definitely get rid of the sand. Your best choices are newspaper, paper towels, carefresh or similar, or aspen. Carefresh is a paper based product and many keepers and breeders use it. Aspen also works well but make sure it is aspen and not cedar. Aspen can sometimes promote the presence of a small invertebrate called a springtail. They are very small and feed off decaying organic material like wood, shed skins, feces. If found just change the substrate and clean the cage. Aspen and Carefresh can also be spot cleaned several times between complete changes.
It is not uncommon for a newly captured snake to refuse food for awhile until it adjusts to its new surroundings. Some will refuse food while their eyes are clouded over before shedding as well. Improper temperature or temperature fluctuations can also throw a snake off feed. If your snake is a problem feeder keep handling to an absolute minimum until it adapts.
Popping was indicated in another response as a method of sexing. This method should be reserved for juveniles only, and many feel newborns only. As a snake grows the musculature becomes more developed and popping poses a greater risk of injury to the animal.
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Firehouse Herps