You need to learn some fundamentals and I think pixelart is not a good way of doing this. By basics I mean, anatomy, colourtheory, composition (whereas the composition is easily the best things about your pictures, regarding the format they are in), form, lighting, more or less everything concerning the depiction of reality (be it photoreal or stylised) through a graphic medium. And don't use the "it's my style"-card, it is obvious you lack fundamentals. I don't mean to be harsh, I am merely stateting what I observe and suggest what I think would help.
Go draw from life, draw your family, your pet, set up still lifes with fruit, draw what is around you. And draw what you see, not what you think you see. Observe.
And about that Sample stuff. It is completely pointless.
I removed it from this picture in like 1 minute, if at all.
I don't know if it's 100% true to your original, but even if it's not it would be enough to rip it and post it as mine somewhere, what i sure as hell wont do

Go practise.