My corn snake isn't necessarily aggressive, just always wants food. Snake hooks are wonderful tools that I use for most of my snakes. My corn will snap at me if I reach for her in her enclosure. I have to use the snake hook and lift her out. Once she is out she knows that its not feeding time and we can handler her without any issues. Maybe you could give it a try. Otherwise just leave your corn snake alone for while. I agree on the brumation thing. Corn snakes do go through it if temperatures have dropped. Signals of brumation include aggressiveness, slow movements (especially in their tongue), and sometimes depending one the morph you will notice them go a little pale.