you do seem to have a good grasp at pixel making, but your main issue is with anatomy.
Taking this sprite as an example, you need to study how muscles and limbs work. The lengths are okay, but looking closely, it looks like they (especially the legs) are a bunch of tied sausages. Where are the joints? They should be defined better for a sprite this size.
Go study real life anatomy, either by observation or with books, study how the muscles and joints connect to form the limbs. It's a really boring process, I know, but once you master some of it, pixel making and art making in general will come out with better results.
Additionally, if you do draw on paper or have a graphic tablet, practice there instead of pixels. Making this type of art on pixels is time consuming, so I feel it is not efficient to practice something as complex as anatomy.
Once you brush up your anatomy skills, I shall teach you more about color composition.
Taking this sprite as an example, you need to study how muscles and limbs work. The lengths are okay, but looking closely, it looks like they (especially the legs) are a bunch of tied sausages. Where are the joints? They should be defined better for a sprite this size.
Go study real life anatomy, either by observation or with books, study how the muscles and joints connect to form the limbs. It's a really boring process, I know, but once you master some of it, pixel making and art making in general will come out with better results.
Additionally, if you do draw on paper or have a graphic tablet, practice there instead of pixels. Making this type of art on pixels is time consuming, so I feel it is not efficient to practice something as complex as anatomy.
Once you brush up your anatomy skills, I shall teach you more about color composition.