I'm looking at your pictures in detail now. The other posters are incorrect I believe. You have a very weak chin. The reason they are confused is that in your front picture the convex profile is being masked by your upturned face. People naturally try and level the plane of the chin and upper lip when looking forward, both to open the airway and for psychological reasons. You need to level the face by rotating it downwards so the line between the top of the ear canal and the lower orbit of the left eye is parallel to the ground, which you've done in your first picture. That's called the Frankfort Horizontal Plane. There you can see that you need quite a lot of advancement for your mandible to catch up to your maxilla. I'd venture that you suffer from the same problems as the rest of us long faced people, which may include the following: steep occlusal plane, narrow arches, underdeveloped cheekbones w/negative vector, posterior crossbite, gummy smile, narrow nasal aperture, steep mandibular plane, hypertrophied turbinates from nasal congestion, and nose deformities including humps and narrow aperture and poor valve support, joint problems. Given the health issues involved, I'd say imaging and evluation by several oral surgeons is warranted to determine how bad your case really is. Unfortunately, there haven't been enough studies done to determine how much is too much, to determine when double jaw surgery should be done over aesthetic procedures like sliding genioplasty to avoid joint damage and sleep apnea later on in life but at some extremes you'll find near consensus either direction.
