What Causes Extreme Stomach Spasms And Slight Diarrhea?

Sat night 2 hours after eating at a co. Sponsored service anniversary diner, I became seriously ill with extreme stomach spasms, no vomiting, just slight diarrhea. Sun am I bought peptol bismol and took full doses every hr and rested. Around midnight sun I began to feel better. Ice Popsicles and Ginger ale today and gold fish crackers. I think the pink prime rib slice on my plate caused this. Can I be tested medically days later?