This to me seems a very sad picture. Although the morning light is glowing warm on him, which normally lends a more positive feel to an image, he remains quite sad looking.
So why does this picture look sad? First, he is looking down, with his head bowed. This pose will add a negative feel to an image, or at least pensive. Less obviously, he is facing the left side of the image, which, to us who read left to right, makes him seem to be looking away and looking back, which further add to the dour feel.