If your guts are reacting to that, it sounds like a good thing, possibly die-off of Candida, or at least stirring things up. You can help things along with an enema, to stimulate the bowels to release the candida. Lots of people have had good results with ACV enemas and seen lots of yeast threads.
Don't take Antibiotics , they'll kill off what little good bacteria you have left! Prebiotics are stronger and more beneficial for gut bacteria because they stimulate our own to reproduce. I'd keep on with it, and supplement with lots of water- you're constipated probably with dehydration. The colon's job is to squeeze the remaining water out of our food before expelling it- if you're dehydrated, the colon will take as much water as it can get, leaving your stools hard and difficult to expel.