Why do your stomach feel like your intestines moving?

Intestines move: food along in order to digest it. There is some air in the intestines, the consistency of the food varies and you can feel the movement. It's easily heard with a stethoscope too.

Gas distension (ugh): The gas moving through your colon causes bloating/distension of different segments in waves, so it can feel like a moving roller coaster in your stomach at times. A large enough stool can also cause the same sensation with more discomfort. Excess gas might be a sign of stomach irritation that needs to be addressed through diet, lifestyle changes, medications, and/or stress management. Good luck.