What Causes Diarrhoea And Abdominal Bloating Post Gastric Bypass Surgery?

I had gastric bypass roux-en Y about 4 years ago. I just returned from a week long trip to Mexico City. I have been experiencing diarrhea, gas, bloating, cramping, and limited nausea. Does this sound like giardia, or could i have issues with my gallbladder which is common after bypass.