To integrate the model with the background, and to get the overall colour tone we want for the final piece, we need to reduce the contrast. Go to Image > Adjustments > Brightness/Contrast and reduce the Contrast to -30.
A useful trick is to duplicate the layer with the model (Cmd/Ctl + J), select the lower layer of the two and use Filter > Blur > Gaussian Blur with a Radius of 45px. Give that layer a Hard Light blending mode. This puts a diffuse lighting effect behind her as if she was really standing against the background.