Let me add a few more things - and Lunatique is entirely correct about the sexualization issue, too. Don’t be a cliche. There’s too much bad art that’s done just to draw a naked female. Rise above that. If you want to draw naked women, then draw naked women, as figure studies.
Now, as to mistakes, you have two glaring mistakes:
One, no background. The gallery here has high standards, and a white background will probably guarantee being rejected.
Two, it’s not finished. You rendered the figure, but you have line drawings of hands in the bottom.
Also, along with your anatomy, you need work on skin tones. Black should never be used on lighted skin. You need to expand your palette, as well, there are more colors than brown, pink, and black.