As some others have said, this reminds me a lot of some old flash games. The music is fitting and the sound effects are satisfying! The visual effects are also really nice. The only things I personally would point out is to make the upgrades less expensive, as they start to become costy very quickly, and also an outline or just being able to see the cursor at all times would be good, since you can't see it well when it's in the dark.
This is very well done, especially considering this is your first jam game! It's quite well put together and just needs some balancing.
Good work!