The first couple of months is really about
adjusting to your new plumbing. Hot baths were the only thing that seemed to help me with the butt burn. And I would sit in one for hours and just cry because it hurt so bad! Slowly add foods and you can pinpoint which foods are trouble, over time you can re-introduce the same foods and won't have any issues with them. The only things that really bother me now are raw fruits/veggies, but I know that Sue's diet is mostly these things. I added sugar to tomatoe sauces and for some reason, didn't have any problems with it after that, I don't know if it reduced the acidity or what, but I love spaghetti! Calmoseptine & Nupercainal are creams that I used, the Calmo has menthol and kind of heats up first and is a great barrier cream and Nupercainal is a great numbing cream!
It's completely normal what you are experiencing, I don't understand why doctors don't tell you what to expect, but in your case, they probably didn't know. I can't imagine how scary that is!
I hope you find relief soon!