You are most certainly beyond "average", which is what I've rated you on Technical Skill. However, I felt there were a couple things that you could push yourself on, if you had felt like it at the time (I don't have the will to paint anything when I'm down about something, thank you for sharing this with us).

The composition- it's dead centre and tightly cropped. I understand that this was very likely a conscious choice, so I'm not too bothered by it. However, cutting her off at the hip joint (or cutting anyone off at any joint) is a little unsettling in an artwork. Perhaps arranging the composition (though this would also mean slightly altering the pose too, I think) so it wasn't dead-centre would also improve the composition?

I'm not too fond of the way that the hair is coming out of her scalp. The shorter clumps of hair look a little rushed in places, and don't seem to be growing right. I don't know much about hair, so I can only give you my general impression. Perhaps studying hair (particularly hair that is strewn about like this) will help make the hair around the scalp look as gorgeous as those locks lying about on the roses.

The skin looks a little flat in places. The neck, collarbone and abdominals could use a little more work, I think, to look a little bit more fleshy and real.

The thorns come across as a bit of a border. Perhaps weaving a couple small thorns in around the roses towards the bottom of the picture will help integrate them into the scene.