I could be wrong but gallbladder pain can often be "referred" or move around to different places like where you would experience costo. I would try another flush and if you feel better afterwards then you will know if it was your gallbladder. I have also found a couple of TBSP of Epsom Salts in a warm glass of water with some juice (to kill the afwul taste) will bring GB pain relief within 30min.