Re: My digestive system has been completely messed up ever since visiting China while on antibiotics and getting diarrhea there (7 months ago).
Did you see your breath test result? And which was it using as the test medium, glucose or fructose? In my case it was the fructose test and although it was negative for SIBO, there was a peak > 90 minutes which means my bacteria overgrowth is in the large intestines (whereas SIBO is small intestinal overgrowth). It's possible he accurately told you that you were negative for SIBO but you still have methane producing bacteria overgrowth. Your symptoms sound exactly like mine. The two main options are
Antibiotics or elemental diets (Vivonex is the main brand for elemental, but you can make close to the same at home for pennies on the dollar). I did both (elemental first), and elemental got it most of the way and the
Antibiotics didn't do any better. And I wouldn't do any
Antibiotics unless it's Xifaxan which is the one that doesn't enter your blood stream like most others. And it's $1200 (and usually not covered by insurance), so I'd look into elemental diets. After the bad bacteria is lower, then it's easier to introduce the good bacteria (the stage i'm on now). But i'm still struggling to get back to normal as mine has been many years of festering and have protected themselves with biofilms (which i'm trying to treat with certain bio-film disrupting enzymes). I'm also considering a fecal transplant, which is something to look into as well if you can't cure via diet/probiotics. For probiotics, look into prescript-assist which is soil based and has seemed to do the best for me. Dairy based probiotics are often problematic for those of us who are lactose intolerant.
Good luck!