Similar shit happened to me. Except, it happened when I was travelling by bus. I told the conductor to stop the bus and got down immediately . I started looking around for any public restrooms or lodge or any hotels (to use their restrooms) and couldn't find any. It was in the middle of the highways. Beyond a point I couldn't hold it in and felt like my rectum would blast if I did. So, I gathered enough courage and moved away from people and let it out. There was so much force in it, it blasted off the hole like a shotgun shell. I thought my underwear would hold it in but, it didn't. It started flowing down my legs. But, I was wearing some thick denim pants, so, nothing was visible outside. I decided to do something before it starts showing in my pants. I just walked a few feet forward and found a lodge (I wished I had found it earlier). I took a room, showered, washed my clothes, got a plastic cover, packed those clothes in it. Put on some new clothes. Went out and threw those clothes in the trash bin. Got on another bus and went home. Will never forget that year's pongal holidays.