I've just spent several minutes mulling over how to phrase my feedback. I was assigned your game as part of the weird "comment pact club" thing that was on the game jam submission form, and I was given advice on how to phrase feedback, but it doesn't help. My own instincts on being polite don't help either. So I'm just going to say it.
Your game feels like a freemium game.
To elaborate, the first attempt at your first level resulted in an never-ending stalemate with one of the robots where I had to give up to progress. The way I beat your first level was to up the firing rate and just overpower the robot. After that, I beat the other two levels by just tweaking my aim with the new guns so that my shots would just barely go around their shots, while switching lanes periodically if it wasn't working. While doing so, I didn't feel like I was using an intended strategy. I felt like I was using an exploit.
The impression I got from this is that the intended way to play your game is to try over and over again, losing each time, until the player can buy the next few upgrades. If that was your intention, don't do that again. Your game needs to be based on skill and meaningful choices before you even consider upgrades. As it is right now, your game instead resembles what I would expect from a game designed to encourage the player to pay money if they want to skip to the good parts.
That's not to say that your game is entirely. I've seen much worse, even from people with plenty of experience. The fact that your game's problems are entirely in the gameplay means that you did a decent job on art, animation, and especially programming. But when you come up with a design, or when you iterate on it, you should be paying attention to what choices and challenges you are actually giving your player.