My pouchitis always begins with excess gas. It is possible to have pouchitis and cuffitis at the same time. I am no stranger to canasa. I put a dab of ointment om my rear and a dab on the canasa. That helps when things are screamingly painful.
I also wonder when your last scope was. I had been having the same types of symptoms you are having. They came and went. Once things calmed down, I learned to use canasa at the earliest sign of irritation. It works much faster then and does not hurt. It seemed I was constantly on the canasa. The longshot of all this is that my doc retired, I went to a new gastroenterologist, and she has quickly brought things under control. Apparently, I have UC in my retained rectal cuff. I suspect I have had it for a long time and my old doc just didn't diagnose it. I have always had pouchitis. After a bout of rotating antibiotics, which helped immensely (My doc just had me on cipro,) she has put me on Humira. I had not realized how bad things were getting. Things are much better now, although I have still had to use canasa occasionally.