Wow! I've never heard of that happening before. Usually, people get the chicken pox the first time, but get shingles from the same virus later on.
The chicken pox virus is never eliminated from your body, so it can make you sick again. I got shingles a couple of years ago, and it took well over a year for the pain to stop--long after the lesions healed. It felt like I was being stabbed in the neck.
Most people only get chicken pox once. I read a statistic once that about 3 - 5% get it more than once. Somehow that information has never made it into the medical school books. LOL
The last two times I got it my doc told me I could only get it once and the previous diagnoses were probably wrong. Then I pointed out he had made the previous diagnosis.
Shingles is miserable. The husband of a friend of mine came down with it. It took a year for it to finally calm down.