Not sure I understand. Did you click on the image in your gallery? The gallery just shows small images and you have to click on them to be brought to the larger image.
I clicked on it and it looks fine to me. You could crop around the edges to get rid of the extra around the sides if you like.
ETA: It is a bit smaller than my layout photos, and that's probably because my photos are large sized files. How big is the picture file you're uploading? If it's a small file, it won't upload bigger on this site.