Hard to tell exactly what is bothering you from the photo. Often people who have a short or so called "weak" chin will have wrinkling of the chin that looks like the wrinkled skin of an orange. This is thought to be from the muscles of the chin working overtime over a number of years. Often a good temporary fix is botulinum toxin. I have attached a link to a photo. Enlarging the chin with an implant can improve the profile but will not fix the muscle issue. Patients often still need botulinum injections from time to time. You need to be evaluated in person to see exactly what is bothering you. Perhaps it is not what I have described.
You are describing something we occasionally refer to as "orange-peel chin." This is a dimpling in the chin skin due to the action of two chin muscles called the mentalis muscles. A small amount of Botox placed into these muscles will relax the muscle and prevent the pitting you notice when you close your mouth. If done correctly, the Botox will not have any effect on your ability to bring your lips together or change your smile. I describe this injection technique in my book, Cosmetic Injection Techniques, available on Amazon.com.
You have a recessive chin and probably also have what is called Lip Incompetence, meaning your lip struggles to close and the wrinkles are probably from your mentalis muscle.
Small amounts of Botox in the mentalis muscle can help. Also my experience is that lip incompetence can be improved with chin implants, so you may get two benefits out of placing a chin implant.
Joe Niamtu, III DMD
Cosmetic Facial Surgery
Sometimes patients with a "weak" or small chin develop wrinkles below their lower lip when they force their mouth closed. The muscle used here is called the mentalis muscle. Developing a wrinkled chin with mouth closure is called mentalis strain. Frequently, a genioplasty can help alleviate this problem.
See a board certified plastic surgeon to be evaluated.