I think the first picture was your best, Kami. Also welcome to MT.
If you want your drawings to look better you have to have a combination of two things: (1) Good knowledge on what things are supposed to look like and (2) good hand-eye coordination to put it down. To improve your first point, I suggest studying perspective and doing gesture work to improve how you see things. Memorizing proportions would also be good since placement of features is really, really key in manga. Learn what foreshortening means and how that should affect the face proportions you draw.
To improve the second point, draw lots! Best of luck to your art.
Edit: Some books you might want to read, if you want to improve: