Hi Delmar,
That does sound like a typical herx reaction. I had the same exact thing happen on Bactrim (which I also had been on prior to lyme and not had rxns too). Naturally, I thought it was killing me so I resolved my UTI using cranberry extract. Then about
5 months later I became ill with lyme. I have since taken bactrim at the end of my treatment only for 1 week or so. I had no reaction to it at all.
Make sure you are detoxing a lot. I think it does make sense to have 'waves' of feeling good and then bad. Bacteria cycle so it is not uncommon to have good/bad days. Just pay attention to your body and if you need to slow down or up the detoxing, listen!
I think that is a really good sign that you are having some good days already.
~beth