Doesn't really matter if it's a song or not, I like your creativity. Sometime's I sit for hour's doing nothing but practicing smooth bowing and smooth string change's without playing anything recognizable, but you do need some work on your bowing technique. Your right arm is very stiff, you need to bend it more at the elbow, do your bowing from your forearm, your upper arm is moving lattereally too much, it should move in a vertical motion instead. Your wrist is not flexing, close up the gap between your finger's, that will let your wrist flex more, bend your pinky finger, right now, it's very straight and ridgid. Check out Fiddlerman's video tutorial on the proper bow hold.

Other than those few thing's, you've got a good start, keep it up.