If I had a dollar for every time I vomited looking at these...
I wouldn't have any money. This is amazing talent, and I think you should continue spriting, for sure. The shading and outlines on all of them are nearly perfect... if not completely perfect. How long have you been spriting? By the looks of these, it appears you've been spriting/making Pixel Art for at least two years.
Ha, I knew it had to be quite a while... the quality of your pixel art is far beyond that of a beginner's. (and many of PC's long-running spriters for that matter).I've been making sprites for...half a year. But I've been pixelling for around 5 :)