/ic/ - Artwork/Critique

When I draw i tend to draw the lower portion of the body larger than the one above (thorax is larger than the head, the pelvis is larger that the thorax, and so on). Do you guys know how to best approach this? I tried to measure proportion but maybe I didnt do it well.
And also about the linework, I know it messy so what do you guys think on how to fix it?
Thanks.