and then I vomited
Proportions, proportions, proportions.
It'll be easier for me to use a visual guide, so I made a quick sketch of the figure in relation to the size of the head (remove spaces in the link if there is any):
The biggest problem here is the length of everything. The legs, the arms, and the torso are way to long in comparison to the width. Legs should be approximately the same length as the rest of the body. Her breasts are also way too low, so if you moved them up, the disproportion of the stomach area would become a lot more conspicuous. Then you'd be able to noticed the arms' problem. Additionally, the lines between the thighs and the pelvic area should stop at the top of the thigh muscle and the belly button should be a bit higher.
What's been really helpful me (and for others) is to reference the actual muscular system, because then you start to get a better grip on where you should draw curves for the muscles, where you should draw lines to indicate the outlining of bones, where the breasts should lie (more straightforward seeming on men, but on women it's basically the same), etc.
The pants are set too low on her hips. The crotch of her pants in relation to her pelvic bone is far too low. This is another area where studying the muscular and skeletal system will come in handy. The hip bones and the pelvic bone make a particular triangle that's a good guide for where you should be drawing your lines.
If you're not sure on whether you've drawn something to scale, try drawing the area without clothing because often times, I've noticed that clothing can make it harder to discern what is and what isn't disproportionate.
Some positives, though, are that the shading is relatively accurate and her equilibrium doesn't seem to be awkward.
You are absolutely right, but it supposed to be like this from the start.
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