It's a nice first attempt!
If you're a newbie to drawing as a whole, I would recommend studying basic drawing concepts before jumping directly into pixel art. To quote the ever-so-true saying by Atnas - "Pixel Art is 90% art and 10% pixel tech".
Try using pencil and paper before using the digital medium, pencil and paper is much easier to manipulate and learn, rather than just trying to force yourself to make pixel art just because you're so eager. Try looking up tutorials, ask advice from people you know, and as always, practice.