This happened to me a few weeks ago:
I was home alone one night (wife working) and I began to get a decent urge to both pee and poop. I was watching a ballgame, so I decided to hold until I really had to get up. I kept eating and drinking as normal while holding. After about two hours the urge to piss was almost too much to take, but the urge to poop was minor. This changed rapidly, about fifteen minutes passed and suddenly I started getting stomach cramps. I held on. The cramps moved lower and I felt a huge soft load pressing on me. I got up and walked to the door of the bathroom, I stood there looking at the toilet letting the urge build and build. I decided to step into the shower to allow my bladder to release first, but my body decided that the urge the shit was much stronger. I was two feet from the tub when my ass opened up just as my stomach gave a huge push. I stood there unloading a huge coil of soft poop. It slowly coiled out on its own, then stopped while some gas escaped, then coiled out again. I was shocked by the amount, it filled my boxer briefs totally. After it stopped coming out, my piss surged out suddenly and splattered onto the floor. I couldn’t stop or even slow my stream. Finally, I was done and I slipped my shorts off. I dumped most of the load into the toilet before washing myself and my shorts in the shower.
I get out of the shower and begin mopping up my piss when a huge cramp hits. I had to shit again BAD. I hated to waste such an urgent one, but didn’t wanna shower again. I decided to go outside. I slipped on some shorts and ran outside holding my butt. I made it about ten yards from the house before I had to drop my shorts and explode. I dropped and squatted as another pile of soft poop rapidly exited my body. It was an amazing night.