In 1992, 2002, and last month, I popped up with a single circular rash. None of them any bigger than a nickel. They did not really itch, they were nearly a perfect circle, dry looking, darker (slightly raised) edge- they just sort of appeared out of the blue.
I thought in '92 that it *might* have been ringworm, but it went away on its own.. and having seen ringworm up close, I did have my doubts. in '02, I was pregnant at the time, and my OB/GYN thought it was ringworm.. I did not. It also went away by itself after a month or two. FFWD to the beginning of last month- I just started to cut back on my abx, after being on them since May of last year. Within a week of doing so, this same type of rash appeared. Same description, same basic size.. maybe a bit smaller (like the size of a dime). Nurse thought it was ringworm, and described it as such to the dr. I knew it was NOT. I showed him the pictures I took of the rash, and he said that since it was going away w/out any type of medication, it could not be ringworm (plus nobody else in my family, none of the animals, etc. have it). What he also agreed with me on, is that it's most likely the Lyme. Obviously it has not gone away (in my case), and things like this can be expected.
I do not think you should assume you've been reinfected.. just that your Lyme is still kicking your butt, so to speak.