Hey, you got something done so congratulations on that. Finishing a game at all for your first try is something to be proud of. The falling platforms are a cool little touch, I like the general aesthetic too though it's a bit unpolished. Expand a bit more on this and you might end up with a cool little platformer.
I'd appreciate it if you check out my game too if you have a minute!
PS - one quick tip for pixel art, it's best to not mix pixel sizes if you can avoid it. Your platforms, stars, and character all have different pixel sizes and that makes it look a bit off.