It’s a viscous cycle. You’re obviously inflamed and that alone can cause pain with a bm. But I’d bet you’re also straining with a bm because swollen anal tissue can prevent a good stool flow and so you push more than you should. That can cause minute tears in the anal tissue and cuff, causing further inflammation and deeper pain. Been there and still trying to prevent it, but I’m also dealing with chronic cuffitis 15 months post take down.