The lamp in the living room

Continuing my endeavor to produce better sketches, I sketched this lamp shade present in the living room of the apartment where I currently stay. The various shades that it produced on the stand when it was lit motivated me to take my pencils and capture it on paper. It took me a few hours of sitting on the couch (in the same position) to complete this. I was left with a back ache after completing this sketch but I think it was worth it, though it can always be better. What do you think??