In the wild, a snake doesn't have the luxury of a feed chart or the ability to pick the perfect meal. I'm not a proponent of the supersized meals for snakes but when a prey item I feed is a bit small, I will follow up with a second prey item and the choice is the snakes. If it refuses, then it waits until the next feeding day. If it were mine, I would leave it up to the snake. Try it and see what it does. In the wild they have choices. I have always given my snakes choices within reason of course. Next time just try back to back with the prey items if they are too small.