The construction probably had nothing to do with it. You should have just left it alone. Some BP's will take a rodent backwards. It's no big deal. Sooner or later they figure it out. Wait a week or so and try again. If he takes it backwards again just leave him alone and let him figure it out. If you're feeding FT zap the rodents head with a hair dryer just before feeding. If live, just let him be.