Same problem here as with your other pieces. I think you traced over a drawing but you didn't take the time to clean up your lines, which gives this messy result when it comes to the outline. Zoom in and see if you can remove some to get crisper, cleaner lines.
Also a pure white background doesn't really bring anything here. Have you tried without?
Keep at it!
Hey!! I know you IRL!! **creeps**
kool pix btw!