Does my voice sound okay?

You're a little rough around the edges, but pretty damn decent, especially for 13. Keep working at it, and as your voice matures you should really have something. The main issue as I see it is your lack of self-confidence; it's not really coming through loud and clear in your style or anything, but still I wonder what you'd sound like if you were really self-assured. (Of course, that's part of being 13.) Hopefully, having a handful of strangers tell you that you're good and you should keep it up will boost your confidence a little. : )