Good question, really. It hurts, but the fear is worse than the bite itself. At least with critters like corns and kings. If you remember having skinned knees as a kid, that's far worse.
My worst biting story... I was handling my little Cal King, then a rather skinny 3 and a half feet. She crawled up my jacket, to behind my shoulder where I couldn't see her head. I reached around to intercept her, and next thing I know, I feel a pin-pricking sting and soft pressure. I withdrew my hand back into view, and there the stupid little beastie was, chomping my finger and wrapped fully around my hand, trying to constrict and kill it.
I looked at her for a minute, hoping she'd realize her mistake. I even said, "Are you going to let go?" And she, of course, didn't. So, I got some water from the sink, and submerged my finger and her head. She tried her darndest to pull my finger back out of the water, still latching on. Didn't feel good, but finally she released my finger. And kept her little body insistently wrapped around my hand. It took about fifteen minutes to figure out how to safely unwind her without harming her. I finally got her back in her cage, and the poor little dear started crawling around, looking very agitated because that mean person took away her "mouse"! I felt like a horrible bully. But on the bright side, I had a neat set of pinpricks, four rows from her upper jaw and two from her lower to show off to everyone the next day. 
Now, I have a spritz bottle full of vinegar in case of any other feeding errors. Better than water. And that was a feeding error. With defensive bites, the snake usually bites and lets go, not wanting to stay too close to whatever it bit. Oh, and the jaw pressure of the little snakes like Cal kings and corns, isn't much. Just enough to grab a mouse and keep it grabbed for constriction.
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0.1 chickens (Condor)
0.2 dog mutts (half ownership, only mine when they misbehave, Lucy & Amy)
0.1 Halflinger horse (Crissy)
0.1 Normal phase California Kingsnake (Sophia)
1.1 parents
Still searching for 1.0 WC human