Welcome bzinbby. I don't know what they are or if it is related but you may want to have your doctor look at them just in case it is something like shingles.
I had one spot that sounds the same as your discription - the black centre - mine was very close to 'tick bite' site - it was many months after the bite - before I had antibiotics - and it did eventually have some 'puss' in it - it took weeks to start to clear-up - but even now - there is still a red/purpleish mark there.
thank you for posting..Patsy and gorbybelle, I also wondered about shingles but this outbreak is only in one area - my sis had shingles and she said it was extremely painful..my rash is just between wanting to itch the area to being just plain bothersome.. I tried anti -bacterial cream..and bag balm...both only irritated it more. I then tried calamine lotion. THAT has worked a little bit. It has dried the area out but the bumps are still there and when the lotion wears off they are still very red. Am seeing my Doctor in a week so hopefully will get an answer. I have no other symptoms with this "rash" so am inclined to think it is something minor. I hope!