I wish I could be more positive, but there are quite a few problems with this game.
First and foremost, everything seems to be pushed to the left side of the screen. There are very few enemies that show up on the the middle/right side, unless it's a large wave, spanning the entirety of the screen, and they only appear in the first few levels. Throughout the game, there are even enemies that are mostly obscured by the left side of the screen because they are pushed so far to the left.
There are some waves of enemies that seem like they should be appearing from the extreme left or right of the screen, but suddenly spawn near the middle with no warning, causing damage to your player. This seems like it is linked to how offset the game is to the left side.
It is nice to have two modes of attack, but having one destroy bullets (wave) and one only damage enemies (trident) makes one far superior to the other, especially when they seem to deal the same amount of damage. I used the wave through the entire course of the game for it's obvious advantages, rendering the trident completely useless. Also, the power-ups seemed to have only worked twice. With the trident upgrades, you receive a (slightly) left and right angled shot after collecting two upgrades, respectively. With the wave, you get get simultaneous left and right shooting balls that get bigger with the second upgrade collection. After that, the upgrades seem to stop working. This is also another advantage to the wave attack, seeing how you get both a left and right attack upgrade, further rendering the trident useless, as it upgrades slower.
Another one of the more major problems with this game is that every single enemy only dropped one coin. Small enemies, big enemies, bosses; every one only dropped one coin. This, coupled with the fact that the upgrades were disproportionately expensive turned the game into a boring grind, especially in the early levels. I had to repeat the first and second level several times to upgrade my attacks enough to beat the second boss.
You certainly have some potential, but this stuff needs a lot of work. I hope to see more of your work in the future!