Cool idea and the graphics are nice! The theme was implemented well.
It seems like the character doesn't really move in the actual 4 directions but rather in the 4 directions of the field (which is rotated)? This makes navigation a bit frustrating. The friendly fire is troublesome and it's unclear where you're placing the turrets. In general the game is very hard due to issues like these.
I noticed you've mentioned the missing music - that would've been easy if you had a teammate. I would recommend you work in a team next time - it's a really good exercise in teamwork and you'll notice you can get a lot more done together.
You did a lot for such a short jam, so good job! This could definitely be a very fun game with some updates.