Sphinchter of Oddi and Loperamide

About 2 years ago I underwent gallbladder removal because of stones. Everything went until about 10 months ago I had some severe diarrhea and took Imodium (immodium). The drug induced an SOD spasm which gave me terrible pain and abnormal liver and pancreatic enzymes for about one week. I have undergone all studies (MRCP, Colonoscopy, Endoscopy, more lab work) and everything comes back normal (liver and pancreatic enzymes are not elevated anymore). The pain is gone, but I have terrible diarrheas or very soft stools. I have been placed under cholestyramine and helps a lot. Questions: the fact that I had a reaction to Loperamide means that I have SOD dysfunction eventhough the pain only lasted while I was under the effect of the opiod? Why could I now 2 years later of my surgery be having bile salt diarrhea? Could the reaction to loperamide create this problem now eventhough I was ok before?
Thank you for your help