Very simple, very straightforward. I liked the music and the fact that you had a countdown.
A couple of the levels made it very difficult to see the black dot. Had to move it back and forth to find it on the screen.
In general, good job - I would say that it may have been a little too straightforward - the only time I even was thrown off at all from the dots moving completely symmetrically, they were already so close that it just happened. But yeah, certainly nothing against it ^_^ Cheers.