I see potential in this game but the lag between the user's input and the gameplay makes it harder to play. Also later try to add some music but make sure it's copyright/royalty free. And finally try to make the gameplay 'smoother' by adding in some transition affects between the moments you spawn and the and go to the next level. Hope this helped you improve the game and help it grow :)
Challenging game. I have just reached level 5. Tough & Funny !