I've seen snakes do things like that before- miss the food & hit something hard (ouch!) & then temporarily lose their confidence. In their mind, I think they think the prey fought back, lol.
BPs aren't the most aggressive (confident) snakes to begin with, which is why you need to minimize distractions & things that may go wrong when feeding them. I'd continue to avoid any handling & interactions- they need to focus on "being snakes". Hang in there.