At least getting bitten by a corn is not bad at all. Thats why they are such excellent beginner snakes, not because they are easy to keep, but because you can learn to handle snakes, without any risk.
Your corn probably wasn't handled very often and thus took a bite at you, or you were handling rodents just before going for the snake. I have a snow corn that is very feisty and regularly try and get me, I just leave him for a couple of minutes, tending to all the other snakes, then go back to him and he is calmer. Just let him get use to you.
good on you for doing the research necessary to obtain the knowledge needed to look after your snake. I have a friend that bought a corn from me, but without doing any research, the snake went with full setup. I told him that he can only collect the snake from me, once he has done at least the basic research on the snake, he is collecting from me next weekend when in PTA again. I wish pet shops would do the same, but some one needs to still pay the rent, so thats not going to happen!