hmm, well an easy way (for me) to figure out lighting, is to hold my hand up to a light source kind of like the one in the picture I'm working on. So if she has light coming from behind, hold your hand infront of a lamp, if the light is from the side, turn your hand to the side. (I use my hand because the fingers cast strange shadows and can help you grasp lighting in strange situations)
thanks... it may very well be inspired by your danish painter... I pick up tricks and stuff from most pieces of work that I see, so even if I don't know it, his work could be what made me think of this colouring and thank you very much ^^