The photos were taken from a bedroom through a window. Post 19 by the OP kind of explains what and why it happened.
Then in that case, floorboards?
It's just a thought...
Most of us would take our camera outdoors, set up on a strong stable tripod, and hopefully in no wind, start the self timer and step away from the camera (or use a cable release or remote control). As the tripod is on a ground, the vibration from your walking around, is kind of damped by the soft earth, plus the vibration goes every where else.
But if it was in a bedroom. You're stepping on the wooden planks, downward pressure on one end of a floorboard plank would move the other end upwards, even if very tiny movement, but surely you know what floorboards are like? Someone else walk around your bedroom, you could feel the vibration from their footsteps? Floorboard creak and groan.
(Even if it was inside a car, your body movement shakes the car, even very tiny, but it's still enough to shake the tripod, which in turn shake the camera.)
We all often want to cut down every tiny movement, mirror lock up, tight and secure tripod head, stable platform, no touching the camera, and all that, and even worrying about a very tiny earthquake, which we did not feel, but is enough for the camera to register a little camera shake.
So I assume a car or even a bedroom floorboard is not even a very stable platform, it may be stable to us, but to a camera, a tiny movement is enough to register as a camera shake? You know what cameras are like, they're sensitive to light and movement.