haha you have posted some in pimp my art thread.... and yes i have pimped some of yours , check it out
OK so far , yes you have major ANATOMICAL AND PROPORTIONAL errors and , many of us trying to make you understand how to make it correct .
I know its too much studies that you will be undergoing but, dont push yourself too hard dont just jump to deeper studies .
I reccomend you that do some FANARTS (you know copying and all) because, you will atleast get a general idea about how are the shapes and structures of different body parts . fun part about doing fanarts is that you can enjoy, critique yourself about where it went wrong . Just copy the original .
After doing many fanarts and what you learned from it apply those in these anatomical studies as recommended by members here . I think that will be more easier .
and yes maybe i will post something for you that might help , so wait for that .