You can get all sorts of weird things happening with gall bladder disease. I don't know if you do or don't retain fluid as a side effect, but I couldn't rule it out.
Here's something I tell everyone: nothing says you can only have one thing wrong with you at once.
If they found a blockage in your bile duct, then yes, the gall bladder is going to have to come out. It's producing stones that are getting stuck and there's no way to stop that short of surgery.
As far as I know, you can't have a blockage in your pancreas. Your nurse may have got her organs confused, or she may have gotten your pancreas diagnosis confused with your gall bladder diagnosis.
I don't know about the left-side swelling. I can't see how that would be related to the gall bladder. That may be a pocket of gas; some people get them in places and they never seem to go away. If you are thin, this would make it feel especially noticeable. The other thing to have someone look for is a hernia. I do know that a bad gall bladder will give you gas problems. I used to get gas stuck in my system and cramp and cramp but never be able to expel it.
My mother had similar circles to have to drive around before they finally conclusively diganosed her with fibromyalgia. I forget how many things they suggested she MIGHT have before they got there. I'm afraid there's nothing to do but keep driving around in circles until they build up enough information to tell one way or the other what you have. That is, to tell what you have in addition to gall bladder problems. Sounds like you do have something extra going on there.