First Impression - the most important one: Its not the dark that got me .. It is an interesting take on the challenge.
Composition: It feels either upside down ... or around the wrong way ... the leading lines e.g. the body seems to take me away from the picture not into it ... maybe a look at either the mirror or flipped image would create.
Subject: It meets the challenge ... but is this really her natural environment.
Technical (Colour and light): Ok dark .. lets talk about it here ... it is dark .. but that does not detract for me nor my partner (I asked him ... kiwipix on here) ... we both feel that this is ok ... but for a portrait I think that people would have trouble with this. I think that you have achieved more than some in your picture, but if you had changed the lighting and perhaps changed the perceived upsidedownness of the picture it would be different ... believe it or not ... it would not be your picture .. which holds its own .. but these are my thoughts.
To grow its vote?: Take a safe picture ... and you will score higher ..stretch yourself and challenge others thoughts and you will grow personally.
Summary: It didn't brown .. which is good ... I think you challenged the norm .. and yourself with a new type of shot. keep it up.
If you've got any questions about this critique, please feel free to contact me via the PM system.
Great idea and interesting composition, but there isn't nearly enough light on her face. It's so dark that at first I didn't even realize she's wearing glasses!
Seems to be exposed for the sky which is great and nice and blue, but I really want to see the expression on the childs face. If this was possible I think it would be quite a powerful image as the angle of the camera adds to the fun the child is having