Would I be a candidate for Genioplasty and Jaw Surgery? (Photo)

When considering corrective jaw surgery it's very important to identify what is causing the excess or in your case the deficiency. The first step is to set up a consultation with an Oral and Maxillofacial Surgeon (OMS) and an orthodontist. It is imperative for you to have specific X-rays and/or Ct scans along with a clinical evaluation  to determine what is your best treatment of choice. Have jaw pain or muscular pain seems to indicate that your lower jaw is misaligned and not your chin. Your photo shows that you have a nice mentolabial fold (fold under your lower lip). This also indicates that your chin is well formed and most likely not the source of the "weak chin".  With genioplasty no orthodontics are required but with lower jaw advancement surgery (bilateral Sagittal split osteotomy) you will benefits from pre surgical orthodontics as well as a few months oforthodontocs after surgery. I hope this information directs you into the right direction. 

If your lower is short, as evidenced by an overbite, you may need to consider advancement of the entire lower jaw for correction. That may be the best way to alleviate your tension headaches. A sliding genioplasty will improve the aesthetics of your chin but will offer no improvement for jaw strain or TMJ symptoms/headaches.

You appear to have an underdeveloped lower jaw which typically results in the 'overbite' issue associated with the profile weakness. Advancing the lower jaw in combination with orthodontics is a basic approach. Consult a Maxillofacial surgeon for discussion.