Welcome to BPNET and glad you've joined us. Please don't worry about being flamed or slammed for making mistakes (most of which I'm sure the pet stores enabled you to do as they tend to give the worst possible information). You're obviously very concerned for your snake and making big strides quickly to correct things.

Once your temps and humidity stay stable and the snake is installed in it's new home (if it isn't already) just let it be for a week or so. Just fresh water and check for urates and defecations, other than that let it settle in and get to know it's environment, it's hides, etc. These are quite shy snakes that can get stressed even when we are trying to improve things so let your snake have it's quiet time to sort itself out with no handling and no attempts to feed during that time.

Did they tell you what the snake was eating before you bought it (hopefully it was in fact eating for them). Also how big is the snake as far as estimated age, length and girth at it's widest body area. That will help you decide what size to feed it, what prey choice you want to make (mice or rats) and what method of delivering that prey (frozen/thawed, pre-killed or live).

Don't hesitate to ask for help or question anything you read if you aren't sure what someone is talking about. You aren't the first nor last person to struggle with some issue with their snake....even experienced breeders have daily challenges with their collections I'm sure They've just gained years of experience with large numbers of snakes that help them know better what is appropriate to do.