Higher

I don't like this sepia tone, but this is the only thing with this image what I don't like. It is not a real thing, even for a sepia, rather an Instagram version of that and this is what disturbes me.

I almost never start a critique with negative opinion, and this exception was made because there is almost nothing I can mark for improvement. <img src="e.deviantart.net/emoticons/s/s…" width="15" height="15" alt="" data-embed-type="emoticon" data-embed-id="391" title=" (Smile)"/> Your pose is magnificent, and the contrast between the softness of the foreground and the bold geometrical angularity of the background is remarkable. The stance puts accent to your grace but doesn't hide the healthy feminine curves. Stretches, but doesn't show you too thin, only ephasize the elastic nature of the youth.
Image composition is nice. Perhaps it wasn't even decided, but combines the central composition with rule of thirds (beam of the window, and body centerline to whole image) and these combinations usually bring more interesting effect, strengthen the impact. The play of light on your body is soft and silky smooth, the fill lights seem to come from the surrounding objects and nothing disturbs the balance of light and dark parts. The overall impact is a strong praise of young women, the window sill functions as a pedestal and the stretched pose suggests springing energy and power. It is about humanity without erotic overtones.

I would be glad to see a pure bw version, but my aversion for the fancy colour shifts is a personal thing, others may like that, too.

Congratulations both to you and the photographer.