What Causes Gastritis And Abdominal Cramps While Having Diverticulosis?

I have diverticulosis and had the first major diverticulitis attack four years ago, though not much since except for occasional cramping and gas. I went on a long trip from Connecticut to Florida a week ago and on the way there had a very mild episode of pain in lower back combined with a feeling of having to go to the bathroom. Though seemingly better now, I still get that pressure in my back and the feeling of having to go. Cannot tell if there have been any changes in my stool, though I had two episodes of diarrhea during the past week. I am hoping this is not the new normal . Any thoughts on whether this could be another diverticulitis episode or something else?