when i first got my corn snake, it didn't eat for 2 1/2 weeks, of course i was worried but now i just figure she was stressed in her new home and needed to settle in. the first couple feedings didn't go so well, in tank, out of tank. by the end i ended up just dropping a pinky on top of her rock hide before i went to bed and in the morning i was happy to see it disappeared. NOT to say that was a good idea by any means, but it worked. now however, i have simply used a tupperware container with holes i cut into the top of it. i will defrost the pinkies by leaving them to sit for an hour, i ust to place pinkies(when she was smaller) into a 20 sac and place it under the tap, & still microwave them for 5 seconds at a time, 2 or 3 times, to warm it up now and then (without singeing the hair thus a bad smell). drop it in, and THEN put my snake into the container. she has had some days where she hasn't felt like eating. but a quick stab of a T'ed pinkie and she always eats now.
I'm sure Kitty biting from the side doesn't mean anything. my snake will do that a lot, then release it, and try again from another side soon after.
if kitty is still young i am sure a 10 gallon will be enough until it hits about a year old. and 2 hides should be enough for now, but keep in mind the more hides, such as foliage(silk) and other decorative things, not only make the Viv look better but act as hides and help to relieve stress on your snake. A stressed snake will have a harder time eating and adjusting to sitting out in the open.
my suggestion, if it was in fact a full regerg is to wait until she is able to eat again. and just leave her in a feed box(with air holes she cant escape from) for a few hours with her prey. possibly stab a FT pinky so some guts are visible. the smellier the food, the more your snake will want it. she should be eating in no time.