Well, I think it looks a lot better colored, but to be bluntly honest, the brightness of the red kinda hurts my eyes, lol. I think what it needs most now is some good ol' fashioned shades. Find the places you want to be shadowed and make 'em a darker color red (it can either be pure red with black applied, which is easy to do in MS Paint, or you could be bold and try a red that either leans more toward purple or orange. Those would be what I'd try, anyhow. :)) But as far as a first try goes, I think you're right on track. Keep at it; you can only get better, after all. :D
Btw, do you just use MS Paint, or do you actually have another graphics program? Because it could be so much spiffier if you could actually touch the whole thing up by editing your lines to make her more streamlined and sleek. :) Just a thought.