Based on your enclosure picture, I have a couple of pieces of advice:

1. With a heat lamp of the same wattage on both sides of the tank, there is no thermal gradient. He needs to have a "hot side" and a "cold side". One lamp should be sufficient enough. If you want to leave it on all night, I would use the red bulb.

2. Your ball python needs 2 hides (preferably identical) on each side of the tank. That way, if he wants to be on the hot side, he'll have a hide there. If he wants to be on the cold side, he'll have one there.

3. Your tank looks a little small. Either the tank is too small to fit two hides and a water bowl or the hide is too big. You want the hides to be snug around the snake. So if the hide is snug, I would suggest getting a larger tank. If the hide is very roomy, try to get a smaller hide and then get a second one to put on the cool side.

I bet his problem is husbandry related. Once you correct the above issues, then he should go back to being his regular self. Also, you can feed in the enclosure, there's no harm in it. In fact, it's probably better and you won't get bit as often.