I think it's really good, I have a few notes for things you could add if you felt like it.
- Make particles that come off of the meteors when they come down that linger for a little while and then disappear
- Make nitro limited, and have things that come down to replenish it,, could have a nitro meter at the bottom
- Make the meteors speed up as you go on (not necessary, would just make it a little harder as you go on
- Make the song not reload when you switch scenes, would stop it from looping
I don't think I thought of anymore, that should be all.
I really liked the sprites you used and how the background had different layers that went different speeds
I also just recently finished my first game as well so don't take my tips as if I were a professional.
hope you find this helpful
(btw my highscore is 22285)