Hi Serena. I like what you were trying to do here, and things get better over time. A bit of advice is what your shutter speed. 1/2 sec is too slow to hand hold the camera and get clarity. It will be too soft or blurry from even the slightest movement. Even if you have to purchase a cheap tripod to start out with it will help you a lot in times like this.
The photo size has already been mentioned, and you will learn the best way to size your images in time. I would also shoot this at a much lower view point instead of being so far above and shooting downward. Try being say a foot or two above the level of the book and angling down a little, but not as drastic as you did here.
So with those three considerations of using a tripod, uploading a bigger image and changing your shooting angle a little and maybe more light...especially on the right side of the photo I think this would have scored a bit higher.
You will pick up all kinds of pointers and ideas here, and learn as you look at what others have done to be successful. Only challenge number 1 so don't fret and shrug it off.
I tried to open this thumb-nail but it didn't work ;)
The composition seems good but it's a bit small to judge properly. I suggest using the full 800 x pixels in future (unless, of course, if this was your intention).