Fun little clean up game! I'm a sucker for this type of top-down spaceship controls, so had a good time blasting around. I also came across the mirror dimension/inverting camera when trying to go out of bounds,
My one piece of feedback would be some sort of mechanic to end the game - be it death, or a timer to see how high a score you're able to achieve in a limit, but I can see you've already noted that in the description :)
Am I correct in reading this is your first game? If so, congrats!