Hi Helen,
Don't want to depress you but it does sound like gallstones to me. I had my gallbladder out in July, one of the best things I've ever done, such a relief.
Back pain is typical. Did you feel you had to sit very upright and straight-backed? That's what I kept doing. Even thought I just had bad posture for a while and then wham, the bad attacks started. Like Eclipse says, very bad pain, takes your breath away. Didn't know where to put myself, and then it just goes, I suppose as the stone gets thru the tube. Yes, it felt like severe indigestion, yes I felt very sick, and like I had a knife in my back.
My advice is, don't ignore it - see your GP and get it sorted out out, preferably before you go on honeymoon. You can possibly get extremely ill if a stone ever gets stuck. This didn't happen to me, but did to my sister, who was in big trouble with her liver as a result of a bile duct blocked by a large gallstone. She is okay now thankfully and the Consultant did say she was unlucky as that is a rare occurrence. So I don't mean to scare you, but I would strongly advise anyone who suspects they have gallstones to get it checked out. Oh yes, and he did say there is a hereditary aspect to it!
My sister and I had both done CD prior to our troubles, though to be fair I think I had had gallstones for a few years before, and I would guess so had she.
Hope this helps.
Sue