Well just to reiterate first I actually really like the drawing itself.
The problem with the shading on it is that it's shading like a lot of cartoons, there isn't a specific light source. On some parts it's like the light is hitting from the front other times from the top and various other directions. It may not seem like much, but improving your shading will help bring your art up to another level.
I'm glad I could help, even if it was only a little. (:
But yes, the candles and the drawers were what I meant by the distraction at the elbows. But I know how hard it can be to get of all that stuff when your background options are limited. The Rule of Thirds is actually a pretty simple. Basically, if you were to draw a tic-tac-toe board over the photo, the goal is to get something in the picture to "hit" the spots where the lines intersect. I hope that made as much sense to you as it did in my brain, haha. Here's a pretty helpful link that might make more sense.
Also, the editing is mostly about personal standards. There's probably a bunch of people who would say you did the editing perfectly (: . I do some editing on my own pictures, and I know how sometimes it's easy to go a little over board.
Overall though it's a really nice photo. I hope I didn't come off as sounding too critical.