You note two improvements along with the worsening of mobility and balance, which in the relatively short time you have been taking abx is good, especially bearing in mind how you were before you started.
I would say that in three months time, rather than stopping abx you should be considering judiciously beginning metronidazole or tinidazole, emailing David first to ask his advice. He doesn't bite: I'm married to him so I should know!
Sarah
