No, you didnt blow it
When it comes to any style of art its almost impossible to "blow it". Everyone has their own style and every piece is unique.
Im a big fan of black & white so ill give you + points on that.
There are a few things that could use some work like depth and focal point.
Depth could be achieved by adding a light source to the piece and bluring or making some parts like the wavy thing going behind the girl instead of on top of her.
Focal point and flow are both equally important, you have some flow but it needs work as its all over the place right now.
The focal point is kind off made weaker by the thing in the top left.
Keep up the good work though.