Nice game, but needs a few tweaks.
Some things I'd change or add.
I'd rather just hold mouse down to fire every chance I get. click spam games are a not ideal imo. The coin count not updating immediately after you buy an upgrade (updates after exiting shop. Prevent the player from walking off the map. Since the play area is so small, lock the camera in a position that allows the player to see the whole scene. running between the shop and the spawner just to find there are a mountain of enemies lol. I think the enemies should not collide with one another, otherwise they can push on eachother when they spawn (one of them landed on my head lol) Oh and the music turns off when you open the shop and never turns back on :(