stock photography is really hard to make money at unless your REALLY GOOD... a buddy of mine is into stock, and he's a great photographer, he makes about 500/month, but it require a LOT of time on his part.. he spends hours doing photos and then hours editing them so that other people will find his photos useful.
with the OP's shot, it kinda looks more to me like, you saw this on the table, took and picture, and thought "that might make a good stock photo" and I think this is the #1 problem with people trying to get into stock... stock photos are not "on a whim" pictures, they are strategically planned out.. the photographer sets up the stock photo, not the photo itself.
I have another buddy who makes a living doing stock photos, thats all he does, he spends his whole day in a studio with a lightbox, taking pictures of things that people need.. he goes out and buys things that people might need pictures of, he invests into stock photography, and because he does that, and puts all the time into, he makes 6 figures a year (i didn't mistype that, 6 figures)
just to give you a FEW samples of what he does (and he's given me permission to do this) heres a couple of his shots:
for this pic, he only had a white helmet, and didn't want to spend $80 on orange ones, because he thought to himself, "i bet people could really use orange helmets as well as white ones" and he spent hours in photoshop to get it from white to orange, and still look natural.
the other key to stock photography is the tags you give your photos... if you just give it 4 or 5 tags, people will never find it.. each of his images has like 30-40 tags which again, he spends time thinking up, so that no matter what someone is searching, there is a high chance they will hit his images.