your criticism is always constructive so I don't mind it. Let the good times roll XD
Others would beg to differ, although, to your credit, you're not as apparently sensitive as they are. XD
The first mistake that stands out immediately for me is how big her right foot is compared to the left. Angles and perspectives aside, it's too large and it's nearly as big as the entire length of her left leg. Even if you intended for her to have big feet, thats fine, but minding the length of the sole better would make this aspect of the picture more appealing and less distracting.
Feet can be hard to draw, some would say harder than hands (although in my case feet are far more easier to draw correctly), so I'm glad that you at least tried to get it right and take a risk that you'd get it wrong than to not try at all and try to take a shortcut or easy way out.
As for the hand, it is placed in a good way, as it is a mannerism showing her shy demeanor. So, the placement and position of the hand and it's fingers are good, but the problem here is, again, the anatomy. The hand is too large. Likewise, her torso is far too long, making the distance between her upper and lower body very obvious.
The thing you did the best here was conveying the right emotion and mood with the face. The blushing was a good touch, and the emotion isn't too strong, either. Combined with her hand gesture, it's gives a good, soft, gentle feeling. However, again, the head is too big when compared to the shoulder area. Even though this becomes a foreshortening issue because of the position she's sitting in, the head is still bigger than it should be.
The shirt strap down the arm is a good sensual touch as is being able to see her panties; it compliments the overall theme of the picture.
You've got the right idea with this piece, and what needed to get across did, but what holds this one back from being all it could have been are the anatomy issues. For beginners, this is usually the number one obstacle to overcome, so it's ever present in alot of artwork. It's something that can only be worked past through study of human anatomy and refinement, and the more you draw the more you'll refine, so keep refining!
😛