Thank you for sharing your drawings. Your colours are really vibrant and your art shows a good understanding of lights and shadows.
My one suggestion would be more practice on drawing things accurately. It isn't that your stuff is bad, but when I look through your artwork, I felt that the proportions of the people drawn seemed 'off', things which are meant to be mostly symmetrical (foreshortening not withstanding) are not, and some things seem to be drawn at the wrong angles.
I too, am learning to draw, and some things I've found to be helpful are:
- Doing more observation before drawing (try to just keep looking at something for a long while before putting pencil to paper)
- Drawing more still life stuff (e.g. an object like a battery, a watch, an apple, etc.) I find it helps improve my pencil skills and allows more confident linework. Plus, if you can draw real stuff accurately, it will improve your artwork no matter what style and/or genre you draw.
- Find some tutorials on perspectives (1 point, 2 points, 3 points). One guy that I've found helpful is Mark Crilley (www.youtube.com/user/markcrilley
All the best!