I added a bit more features, and tried to shadow in a bit more. It doesn't look horrible, but it doesn't really look good either IMHO. What do you think?
I don't think it is looking bad—it usually doesn't start looking good until you get the shading looking right. I would say the colors could use more contrast though. It looks like you are already using 4 or 5 grays but the change isn't that notable.
If you are a beginner then I recommend starting with smaller size (like 32x32) and limit yourself to 3 shades for each color. At least that is what seemed to help me.
I admit, this doesn't look good, but I drew a cat quickly using only 7 colors and its under 20x20 sized. (probably could have gotten rid of one of the grays, too). Smaller sized canvas will take much less time but you will still see improvement.
(I think it looks more like a dog
said it doesn't look good—I need to practice drawing animals!)