Constant Intense Burning Left Chest 2yrs Shingles????Anyone had this

For the past 2 yrs I have suffered with unbearable left sided chest pain, its not on my skin it feels like its in and around my left breast. I have had every test imaginable, ct scans, bone scan, mammogram, breast ultrasound, heart tests, nothing has come back abnormal, all my blood work is fine I even had intercostal nerve blocks that only numbed be for a day and it was back full force,  I am suffering everyday of every minute of my life with this awful burning intense pain that never ever lets up. My Dr's are thinking post herpetic neuralgia because around the same time it started with a slight burning I had about six blisters in the center of my chest right where my bra is and I remember them being itchy but never gave it much thought after that but this intense pain thats been just getting worse and worse over the yrs is just killing me and my life is not the same anymore and I dont know what to do. Has anyone ever had this and was it from shingles?? Please please I need some insight on this..and its not heartburn.....Thanks... shine