I really love the game
And the fact that it's your first game is impressive
The idea of the game is really good
Here are my suggestions since it's your first game :
Don't use the default font for the game
There are some fonts available on google font
Maybe you can give them an outline
You can put a description for the upgrades so the Player knows what it does
Overall, really impressive
I also liked the UI of the main menu , it's really well done .
I didn't have enough time to publish my gsme
So congrats on publishing yours