The game has quite a few features which are well implemented, such as the different towers, enemies that shoot as well as close combat enemies, an upgrade system and a huge variety of combining those upgrades. Great job on implementing so many features in a week!
That being said, the game also has a few flaws which I'd like to mention so you can work on improving it. :)
- The graphic style has no consistency. The anime character felt completely out of place, the player sprite is ok but if you're already using pre-made assets, try to go for one consistent set and try to match any selfmade assets as good as you can (I know, matching someone elses style is hard)
- The game needs a tutorial. This could be at least a few screenshots and short descriptions on the game page or as a pdf with the download if not in the game itself. I placed some of the towers randomly by clicking on the icons and by accident defeated the first wave. With the first upgrade selection I realized, that this is a tower defense game. The upgrades also gave me the hint that my player is able to shoot so I tried buttons until I found Q. Why not the mouse button if that's what you're already aiming with? :)
- The song does not repeat so after a few waves, you just play in utter silence except for the sound of your shots, which unfortunately do not sound that great.
- The countdown on the towers should be counting down, not up. It's unclear when the tower will be available again.
- Last but not least, the game needs to be more challenging. I made it to wave 12 and then stopped because the cookies didn't get closer for 3 whole waves even though I hadn't placed any more towers since then.
Hope my feedback helps you improve on your game! :)