Hello, I am a 43yo male in good health overall (workout/run 3x per week, non-smoker, normal weight, not on any medications). For the last year or so I've noticed that occasionally when I urinate or have a bowel movement I will feel something in my lower left abdominal area that seems to shift or move within that area, almost like a marble that is moving back and forth within a confined area. Over time this "marble" seems to have gotten "larger" as the shifting/movement seems more pronounced.
I experience no pain or discomfort, just something moving. I occasionally experience this as well when I blow my nose and perform certain exercises at the gym. My bowel movements and urination are completely normal and have not changed over this time. The lower left area of the abdomen (approx 6 inches below the navel) also seems slightly larger/bulged than the right side.