Hey!
Thanks a lot! Don't worry about donating, I'll still work on the game as long as I can even without donations :-D
I added 2 levels in the Christmas update, but these aren't "real" level, they're just previous levels with a new game mode and different enemy spawns. I'll try to ask a level designer friend if he could help me with levels so that I can focus on code and game design and have a reliable way of having levels regularly added to the game.