This will be my first post and maybe it's not appropriate to give advice, but... 
With such a small number of pixels, you really do need to exaggerate the features that make a cat look like a cat. What you've done here so far doesn't need drastic edits to fix, in my opinion... i just made some subtle changes to it. The ears. And a visible tail (kind of runs off the bottom of the frame, and may be more fluffy than you like, but.. that's the idea).
Sorry if i'm out of line.
Anyway, those ears are probably kind of big for a real cat, but i think it works to define the features of a tiny sprite.
With such a small number of pixels, you really do need to exaggerate the features that make a cat look like a cat. What you've done here so far doesn't need drastic edits to fix, in my opinion... i just made some subtle changes to it. The ears. And a visible tail (kind of runs off the bottom of the frame, and may be more fluffy than you like, but.. that's the idea).
Sorry if i'm out of line.
Anyway, those ears are probably kind of big for a real cat, but i think it works to define the features of a tiny sprite.