TMI poop problems

Kinda long sorry. Ok so I went to the bathroom at Sears, and I had a bowel movement needing to happen. But everytime it got close to coming out I had this giant Charley horse in my butt cheek that prevented me from being able to go. It would cramp up and get to the point where if I didn't stand up and work it out I would cry out in pain. Seeing as I'm in a public restroom I can't exactly start crying in the stall. Eventually I gave up and walked around the mall, tried again and managed to evacuate some of it but it just feels like there's something left and everytime I tried to get it out the charely horse thing would happen again. I tried just sitting there and not pushing but nothing would come. Eventually I once again gave up and left. Ever since then I feel betterish. But still having the you gotta go pains in my back. Which do feel slightly similar to the back labor I experience had the other night. (Labor started but stopped)