Wonderful timing. Really fabulous. I wish you had used a more even backdrop and adjusted the lighting so it wouldn't be so glarey on the surface of the tiles.
A moment frozen in time. Technically competant, the lack of motion leaves a static impression that, while not negative, isn't positive either - it would help to have some movement to express the idea - this image gives an impression of being a "trick" image rather than a natural physical action/reaction. A good solid entry into the challenge.
nice idea. The background does not help the image. It would be easy to hide it by sticking a sheet of plain paper to the edge of the table - or maybe even an open newspaper as if someone were sat at the table oblivious to the falling dominoes - just a thought. good luck