Bile Reflux?...No gallbladder...Barrett's?

I had my gallbladder removed 5 months ago due to a gallstone. Still been having some of the same symptoms plus several new ones.  Experienced heartburn several times which had never happened to me before.  Still have abdominal tenderness, chest and back aches, burping, and lots of hiccups.  Sometimes I will feel this achiness in my chest and almost up to my throat which happens sometimes after eating.  When I wake up in the morning I feel just a little bit of nausea.  When I get up and start moving around, my chest will ache a little, and get much worse if I attempt to eat breakfast which will make my chest and back ache.  Have to wait til around noon to eat.

I had an upper endoscopy last week and my doctor said my stomach looked fine but that he found irritation in my esophagus.  In fact, he said Barrett's, when describing it and said I've clearly been having reflux for awhile.  I've taken Prilosec, Nexium, and Prevacid over the last few months and haven't gotten any relief.  Also have been taking Carafate for 2 weeks.  He thinks that just maybe it's not acid reflux but bile reflux that I'm having so he prescribed Ursodiol to see if that will help. I'm to take it for a month and if I'm not improving, he is going to refer me to a gastroenterologist,  I've been seeing the general surgeon that removed my gallbladder and he performed the upper endoscopy.

1) How long would it take to Barrett's to develop?
2) I'm only 26 years old, is it rare to seem Barrett's in someone my age?
3) Are there tests that would distinguish between bile and acid reflux?
4) The only times I had heartburn was when I was taking PPIs.  Could I have been having more bile reflux while taking those since they just suppress stomach acid? My doctor didn't tell me to take PPIs while taking the Ursodiol.
5) Would not having a gallbladder cause bile reflux?
6) Is it likely that I'm experiencing bile reflux or could something else be going on?
7) What does Ursodiol do for bile reflux?