Animation (Drag, weight, recoil, etc.)

[Bombshell93]

as the title suggest this topic is aimed around animation, I've recently wanted to try out hand drawn animation but my graphics tablet died, but I figured I could practice base principles via pixel art.

I'd like to stress, I do not aim to shade these sprites, I aim only to get good animation quality. Colours picked and line art problems are ofc still relevant.

Here is the sprite I'd like to start with, aiming for heavy recoil animation like a cartoon, to exadurate obvious features.
OLD

Spoiler

CURRENT
EDIT: a slight revision

I've made a little progress but I see a few problems, namely the shoulder of jelly, I'll fix it up soon, any more comments or criticisms would be greatly appreciated so I can work on other issues too,
thanks again for the help

any and all comments, constructive criticisms, advise, relevant links and or references are greatly appreciated,
Thanks in advanced,
Bombshell