i'm not a caricature specialist, but i have some crits that could perhaps help.
Your drawing appears to me like you just distort the original material in a way to make it funny, but without representing credible volumes. Like a photo manipulated in photoshop.
the right ear of the man is the continuation of the cheek, on the same plan, in reality the ear is far from it, and we must feel it even on a caricature.
Caricature must have credible volume, so the main thing is that you should work and make sketches to get a comprehensive approach of those issues.
The 3 drawings have the same problem of right ear looking like it's not behind like it should be.