I gave it another try and got frustrated again in 30 seconds :-(
This is a classic case of you playtesting your game, it happens to me too, we are the worst playtesters of our game, because we made it, we know all there is to know, how to optimize your mechanics, how to speedrun, what the best strategies are, where the enemies are.
You are an EXPERT in your game, clearly, but for me, and apparently for the rest it was very difficult, assuming we only have basic FPS knowkedge and know nothing about your game. I don't know if that's what you were going for, but just to let you know. For me the fireballs were too hard to dodge, it's a barrage of fast bullets that don't even let you slip between them, the platforms are too pixel perfect (you need to learn about something called "coyote time") and the timer is unforgiving, starting with just 10 seconds, and the upgrades just give you 2 extra seconds which doesn't give you time to pause for even an instant.
Thanks for the gameplay, it does show that you playtested your game A LOT and you became an expert in dodging fireballs and precise jumping,