I sympathize- I had an absolutely awful few weeks, 2-3 weeks of sheer hell. This was the first 2-3 weeks after an infusion, which are normally failry good times for me. I didn't know what was going on- I had quit Culturelle & started Primal Defense Ultra. I thought I was getting my period. I figured maybe the seasonal flare aspect. After 2 weeks of torture, I quit Primal Defense, went back on Culturelle, & added another high bifido probiotic. And lo & behold, things are back to my normal! I've been sick also, a weird head/sinus cold- but I'm just thanking my lucky starts it's not pneumonia again, or some other repiratory infection. My teeth have always been pretty good, so I can't help you there- I've never had a root canal, but I always figured I'd opt to get a tooth pulled before going thru one. It may be your best, at this point. Hope you feel better soon!