Yes, feed in his enclosure. I dry the rat with a hair dryer and I don't have to worry about aspen sticking to fur and snake swallowing aspen with rat.
You will have to find a vet that will treat a snake and that has experience.
If you feed him a mouse, he might not go back to rats. Someone correct me if I'm wrong.
I don't know if they smell fear, but they do sense if you're tense/nervous by the way you move your hands. I mean like hesitation and that makes them nervous as to your intentions. "Is she trying to hurt/eat me?".