I had back surgery about 2 months ago and three after surgery I developed a bad case of shingles on my left thigh same side where I was getting pain before surgery. It's going on 3 weeks and although the blisters are gone I still have some crusting on my thigh and the pain is still unbearable. How long does it take to completely rid the shingles pain. Are there injections that I can be given for the nerve roots so I won't have so much pain?