Honestly: To post in here, please actually check and check over your sprites, do they look like official sprites? Are they actually good? I can't say they're good, because they're just not. They need work. Shading, outlines, feature connecting. Don't bother with the shop, there are many shops out there, and some are better. You'd just get worked up with it.
Suggestions are, practice and see if your sprites look good.