Updates:
I had the pouchoscopy, unsedated for the first time, and it was okay. I did struggle to do the enema prep because of pain with insertion (which I did not experience last time I had a scope with the pouch and used enemas, so I don't know what the problem is there.)
The results are positive. No inflammation in the pouch--no sign of pouchitis or C-diff, no swelling, and no strictures. Lots of nice pink, healthy tissue.
So, the good news is that there is nothing seriously wrong. My symptoms have improved so that the pressure is gone, and I am emptying a little easier.
However, I still am not able to pass gas normally. It doesn't really cause much pain, but it is a strange, new annoyance. I have not dealt with that since takedown (and even then I could pass gas on the toliet with a bm...now I can only do that rarely. No idea why, since there is nothing obviously wrong in the pouch.)
I do not have more gas than normal, but it is more difficult to pass. I also still cannot seem to empty with complete, normal ease. I am hoping that I continue to improve with time though, assuming it is somewhat related to the mushrooms. The GI did say there was some fibrous residue in the pouch--which, since I have been eating a very low-fiber diet for the past few weeks, is strange. I am still eating things like cooked onions and herbs/seasonings in food, and I really, really don't want to have to cut those out of my diet too. I love veggies...sucks to have to cut everything out.
Seems like the only theory right now is pregnancy constipation caused by the ramped up progesterone production during pregnancy. Except, of course, my constipation is worsened by fiber. Most pregnant women are told to eat fiber for constipation. Not me. It is weird that pouches are so unlike colons in that way?? It does seem to make since. My symptoms started right around the time I conceived, before I even knew I WAS pregnant.
Because there's nothing "wrong" with the pouch, I was just told to eat a low-res diet and wait it out. I am thankful that there's nothing seriously wrong. I am also thankful I don't have to take an antibiotic during pregnancy or have surgery. However, I am a little disheartened that there is no real diagnosis or treatment. I have been eating pretty low-res for weeks, and while I have improved, the improvement is not 100% yet.
Thanks for all your comments. I'll try to update if anything else comes up.