I have a 3 black spots on my mid back that started as pimples and were very itch. soon one heals another one pops up. I have 3 on the right side of my back along the spine, one in the middle of the spine and one on the left side along the spine. 2 of those have a dull pain on my mid back. what could it be? I have had both chicken pox and shingles in the past. could it be a recurrence?