I am being paranoid. My husband says so too but I have a subsidence fear since noticing a small internal crack. My husband and surveyor say all houses have movement but how much movement is normal? I like sitting on the floor by my bed which is on the first floor and whenever someone walk across the room or another bedroom, I could feel slight movement on the floorboards. My family have heavy footsteps so when they step down on the floorboards I could feel a slight dip. I checked the ceilings downstairs and all felt firm. Is this kind of movement normal?