I couldn't open your picture. It comes up blank. It's labeled as a JPEG, but the picture looks like a BMP file.
Not sure of your specifics, but you will have a few first reflections. Unless you have a VERY wide acoustic panel, it probably isn't covering all your first reflections. In my room, my first reflections cover most the side walls from the front to the listening area (give or take). That's because I did it from all three seats in the front and back, and not sure your setup. If you do the mirror trick, remember to do the first reflection for the Left Speaker, the Center Speaker and the Right Speaker on both side walls. It's good to cover the front wall as well, so if you have extra, you could use it for the front wall.