Very simple and the artstyle and music are nice for such a short time
However I don't like games where I have to take damage because I just can't avoid it - so for me to enjoy it you would have to either:
make the circle way more responsive ( maybe turn with the mouse so I can turn much much quicker)
or:
make it so the some colour doesn't spawn on three different sides so that they arrive at the same time.
Alternativley you could tell the player which form has what effect so that they can make an informed desicion....