I see that this is your first post, so allow me to welcome you to MLR(!) and direct you to the
introduction thread, where you can say hi to everyone and be inundated in replies if our regular topic-spammers happen to get on anytime soon

And now, on to the track. WHY IS EVERYONE BETTER THAN ME AT MELODIES

But seriously, I really like the melodies and how much you varied everything in this song, it really keeps it interesting the whole way through. And it's so happy!
On the critiquing side, though, beyond your admission that it's not mastered at all, I'm going to tell you what I seem to tell every newcomer: Do some sound design, because it'll lend you a voice of your own to use in making your music that's more obvious than a composition technique or the like. Watch some Youtube tutorials if you have to, start out by tweaking synth presets if you have to, but a good thing for new producers to work towards before much else is a library of your
own sounds.
You might also want to look into getting some packs of samples and the like, when you get to the point of learning drum processing and all that.
But for a first song, it's pretty good, and enough to make me interested in where you'll end up as a producer
