First of all, for a rookie photographer, you are progressing wonderfully. I can see where you going with the picture and the originality of her pose just screams seductress. I have go to hand it to you for how perfect you were able to catch her mid motion because the photo screams wow. you did a spectacular job with smoothing out her skin and sharpening the umbrella in PS (if you did that is). Again the impact is just very stunning to a point i just can't seem to find the right words to describe such beauty being presented.
The idea of the red umbrella against the black dress wonderful. I love the angle you did it at as well. The only advice I would really give is that the model should stand a little taller. She look very short right now, even in heels. Also, it might look very interesting if she wore bright red lipstick. As for the background, I absolutely love the fact that she is so dressed up on such simple grounds. The bushy plants look wonderful, and set it off. The location you chose was very clever. All in all, I love the picture.
Love your gallery, especially love this pic She's beautiful and looks really attractive in that dress (I have a weakness for girls in black dresses of such type), plus everything else blends into the pic well. Well, the umbrella stands out, but it looks really cool and makes a great detail in the picture overall.