Those littlel bulges are pockets of gas. They move around. Sorta like being pregnant and watching the bady's foot, fist or knee moving was what they reminded me of. Except I don't remember any of my kids being so spiteful as to make it hurt so much as when those darn gas bubbles move thru the small intestine!!! Hey, the small intestine wasn't made to stretch THAT wide and thick!! It hurts! They aren't just little gas bubbles by any means!!! Generally, after one would move thru and sorta melt away I'd hear or feel gurgling from the area. Little bitty gas bubbles moving thru as the big one breaks up.
Speak of watching the abdomen and movement thru the small intestine .... did you know, if you are on the slim side that you can actually see the scope moving thru your colon during a colonoscopy?? You'll see a red light thru your skin as it snakes along your colon. Especially down the ascending colon on the right side to the ileocecal valve where the colon is closest to the outer surface of you body.
See? You learn something new every day!