like punk rock... on a piano...
not that it doesnt sound good but... you're only sticking to 4 base notes and creating variations on the treble. And besides, going down a half-step on the bass makes ANY song sound like "Stairway to Heaven" OR "Tears in Heaven", so its already a bit cliche unless you have a whole chord structure on top of it. The melody was creative, but got boring quickily. Work on rhythm, maybe try playing like really high pitched notes on the offbeats (kinda like snowflakes falling and touching the ground, i guess?). Good work but... you can do a better job.