I feel for you. I spent years on PPIs and because of that I believe I developed IBS. I currently take Pepcid AC 2 times a day and the back and rib pains that you described are less severe, but still there at times throughout the day. It took me about 6 months to ween down from a prescription PPI to the OTC Pepcid AC. I typically get mild heartburn from about 2-4pm. I take my second dose around 530pm. I believe that if I could get off the Pepcid (H2 Blocker) the IBS would improve, but my heartburn would be worse. I already have a very strict diet, chew gum, drink alkaline water, take suppliments, sleep on a bed wedge, I follow all of the rules. Some times I am fine other times more painful. I wish I had the answers. All I can do is take it a day at a time and continue doing what I am doing. Nonetheless, I am still concerned about pregnancy.
GERD Moderator; Diagnosed GERD, possible IBS; Gluten free since 2012; low lactose since 2012