This is a lot of fun! Pretty damn good for a first game. I’m actually surprised I’ve never seen Snake and Tower Defense combined before, you are onto something imo.

It might be helpful for this style of game to move the tower to the left hand side of the screen, so you have more space to focus on the enemies. I’d like to hear some music and sound effects added to the game as well.

All in all, great concept and you executed it well :)