Hi Libby,
The composition is too static. Should have worked with diagonals, triangle or zig zag composition to lead the viewer more. All the action is up top with the figures and colors. Second figure should be closer to the bottom of the page or you should have not left so much space at the bottom and sides. The negative space has no fight with the positive. For an exciting picture they should push and pull each other, this can be done in your work without killing the theam or mood.
The technique is good though. I can feel the dreary day. No need for a lot of shawdow.
Hope this helps,
Jon