What Causes Stomach Pain After Having Soda?

Everytime lately that I drink club soda I get intense gut pain. I overload with probiotics, activated charcoal and pepto bismal. Thinking it was the vodka. So I tried just making my drink with water and fresh pineapple slices a touch of lime and I was okay. So I tested again yesterday and within an hour of my usual drink Vodka, club soda and a touch of juice again I had the gut wrenching pain within an hour. I have been drinking this mixture fora couple of years now and never had this symptom. What would cause it now? It is the same brand od club soda I have always used.