Hi Wiseguy,
I'm also in my 3rd week of Doxy with no herx. Not everyone herxes on everything. In the 16 years I've had Lyme, I've only been on antibiotics for a max of 3 weeks at a time, but I don't ever recall herxing from them. Since I wasn't diagnosed until last year, I will be starting an herbal protocol soon, and I anticipate herxing on that, as it's fairly aggressive.
As for candida, this, in my opinion, is the best protocol: you need to find a loosener (biofilm detox) like boluoke or bromelain, and rotate 3-4 antifungals (like garlic, goldenseal, pau d'arco, oil of oregano, caprylic acid) so the candida doesn't develop immunity (it will develop immunity if exposed to the same antifungal for 21 consecutive days). While on the antifungals, do the candida diet to weaken it. Diet alone won't kill it. Avoid vitamin D and calcium in particular, as these feed candida. After 3-4 weeks of this, start on a good pro-biotic to recolonize the walls of the gut with good bacteria. If you start on the probiotic before the candida is gone, it cannot populate the gut walls because the candida is in the way. Slowly begin adding in foods over several weeks' time--small amounts of fruits, then grains, then dairy, and eventually back to normal.
I do not recommend trying to do a candida protocol while on antibiotics. The best thing to do is to take an antifungal while you're on the antibiotics, as it will help keep the candida from getting worse. When you're off the antibiotics for a long enough period, then do the candida protocol.