This looks suspiciously like a color reduction or photoshopped piece. The shadow has a huge number of colors and the "pixelled" part has 91. Even if you did this by hand, it needs work, especially in color conservation. If one pastes one image over the other, the outline of the shrimp deviates in only a few areas and several of the details are identical in shape. If you didn't reduce the image's colors, you traced over the outlines, a practice not smiled upon. You gain no skill from putting pixels right where they already are, and it won't get you very far in this community. Additionally, don't use tools to draw shadows or anything else.
I think the best thing to do in your position would be to redeem your reputation with some pure-pixel works or a progress animation that shows how you made this, using pixel-perfect tools (pencil, fill bucket, line tool, no auto antialiasing or gradients). Hopefully this is all a misunderstanding.