The first thing I noticed was that the proportions are a little off. I would suggest taking an anatomy class or doing what I did and just keep looking at pictures and or pick up a "how to draw" book or anything like that. Also when I was first learning how to draw I used to trace things a lot, and after a while I have been able to draw those things from memory, it's a really helpful thing to do if you can't afford anything else. But the pictures look good :3
please comment or critique my art Here if you're willing. Thank you!! and good luck!