It's Lacking
Well, the graphics are borderline not good for one, but my biggest problem is that it's mindless.
You have no instruction explaining that missing loses points. As simple as the game is, you should always have some menu where you can read instructions. It's just more professional.
Also, it's pointless. By that I mean, you're seemingly on a farm and targets are falling form the sky.
What?
Make it birds flying by or animals running by or something that makes sense.
Also, the green blobs make no sense. The targets are white and red. Also, the blobs block what you can see. Make their opacity 50% or less and NOT green.
Good luck, but this isn't very good as it stands.