Good, but not enthralling
The picture you paint is not nearly bleak enough for him to rationally quit his job. If he is supposed to be sad, he doesn't seem to be. The fact that he is depressed about the girl... is all his fault and this story has no protagonist. For that reason, people will not have any emotional stake in this and leave without much of a feeling. Here's the plot: a guy is good at his job, but doesn't love it, so he quits to pursue a hobby. His emotional and mad rejection at the end does not follow a natural progression of anger that should have been built up. In order to fix this up for the contest, the only thing i think you can do is not have him quit his job and let him find the balance perhaps by adding a scene where he gives the girl or a kid a beautiful piece of origami.