Take them back. Caring for wild caught snakes that don't have established care guidelines is too much for a new keeper. I doubt the shop charged you much for them. Your first vet bill will undoubtedly be higher. Don't throw good money after bad. Return these snakes to the shop. Even if they won't give you your money back, you'll be way ahead.
And the money won't be the half of it. Frustration and concern over their declining health will give you grey hair. More importantly, it will keep you from attending to your new rat snakes. Do your research first and I'm sure you can find much more suitable snakes to fill those new enclosures.
What we're describing above isn't a worst case scenario. It's the most likely scenario. Don't feel too bad. Your not the first new keeper to fall prey to an unscrupulous pet shop owner. Most new keepers do. I don't know you, but, if you were my own brother, I'd give you the same advice. Good luck.