I would double check temperatures. And make sure everything is where it should be.

Depending on the king snake, they have an attitude. And expect to be bitten if you have handled another snake without washing your hands.

If you feed them every time the act hungry you will end up with an obese snake. In the wild they eat as much as they can in one sitting because they don't know when the next meal is coming. As pets they have a constant stream of food so no need for them to eat so much so frequently.

You will not under feed this snake by feeding a hopper once a week.