I like the music (although it loops a bit too obviously) and how it looks. The big problem here is that the actual game play isn't actually explained. At no point is it made clear that you're able to double/triple jump. When you die, it would be awesome if there was something telling you what happened. Where it stands it's never really very clear why you're dying. Definitely potential and the code seems to work, I think there's just a few user journey issues that you'd profit in updating.
Good luck in your future ventures!
Good idea, BUT...
I'm giving this a 5 because of the crappy collision detection. It shows promise, though. Combining the usual run/avoid with upgrades was nice, and the artwork is good. The other problem I've noticed is a bit of grammar derp on the 3rd level with the signs. "It's will be hard"? Now I realise that you're from Latvia. I'm just pointing out something that others will eventually if you don't fix it. My advice is to fix the collision detection and the grammar, then resubmit.