Yay, I managed to reach Wave 15! Once you manage to fully deck out your ship, you can keep going for quite a while.
There's some neat things going on ever here - so many particles! So many in fact, that the game can start lagging slightly, but I guess bullet hell has that appeal. And all the turrets and upgrade system seem to be working correctly, so good work!
Beside the lack of sound effects that would've tied it together well, I noticed you sometimes don't see the enemies on screen? Is it intended that you have to buy either the small or big red turret in order to see them? At least the AI knows where they are...
plus it's hard to shoot them as the player anyway - they go so fast!
All in all, not a bad game! Would just need some extra finishing touches, but for a Jam entry it's very understandable.