i dont think you can tell if your plant is female yet,if you see the white hairs in my photo,thats what your lookin for,might have to put it in to flower first
i think the change of colour to the leaves is just a build up of nitrogen in the leaves,think its telling you that its got enough nitrogen for now(im sure one of the experts might be able to tell you for sure)
and the strain of my plants is bigbud