Alright. so you don't necessarily want to make the mouth too big, unless you want to exaggerate expression, which is totally fine. I do also notice that it looks like her neck is in the middle of her torso, which doesn't really make too much sense, unless you're going for a monster/alien/mutant kind of look. You can completely ignore my advice, I won't get hurt. Your art is amazing, though and keep up the great work!