great work! love the attention to detail!

you have a few proportion and anatomy issues. You can get better at that with time and practice.





if you're interested, you can use Andrew Loomis' "Figure Drawing For All It's Worth" to get a better understanding of how to draw better anatomy. It really helped me out a lot

Or you could refer tutorials on youtube channels such as Proko or Draw With Jazza. there are also a lot of tutorials on deviantart which you can find in the "tutorial" section