I only suggest feeding two prey items if they are both f/t. Feeding live twice is a huge expanse of energy for the snake and could cause regurgitation.
Are you feeding him inside or outside his enclosure? If your feeding him in a separate enclosure, this may be enabling him to bite you more.
If he's a strong eater, try getting some f/t mice and see if he eats them. Most likely a jump from a adult mouse to a large rat will be too large of a jump. On f/t, you can find more of a variety of rat sizes. A weanling rat would probably be a good size for him.