This game has a lot of potential and a great premise, but definitely could use some polish/extra playtesting. I mention playtesting primarily because of the part where you need to shoot the explosive arrow down a narrow shaft, which was the most tedious part for me. I don't know how much difficult it was for you during testing, but a good rule of thumb I like to follow is "if it's just hard enough for the dev, it's too hard for the player".
Others have talked about the unforgiving nature of the core mechanic and awkward controls so I won't mention those much, but I will add that this kind of movement control really doesn't work well when you need to dodge more than one projectile at once like during the boss. I also noticed a bug where if you aim the second dash while you're flying upwards, you keep flying upwards without losing speed/momentum. I think it could be improved by removing the delay before your dashes recovers after you land (so you can jump again as soon as you land), and slowing down time further, or even pausing time, while aiming so you can better dodge enemy attacks and aim yours.
I don't think you need to scrap the game completely as some have suggested, but some changes are needed if you want to continue with this for sure. Even if you decide not to continue this game, I still think you can learn a few things by fixing up some of the issues I and others have pointed out. Game dev is hard work and you're doing well, don't be discouraged and keep it up!