OK, probably paranoia, but we've had an single storey rear extension recently built which has involved some hefty steel beams going in the back of the house. DCs bedroom above this has tiny hairline cracks across the side wall, that will likely be covered up with paint. And the doors have gone weird- our bedroom door facing to the back used to swing open fully if it was partially open, and now stays still, whereas the bathroom door facing front now swings open if it's not latched when it never used to?!