I got this with my last pregnancy too, but never quite figured out what it was. It's not the baby moving because it's up too high, just to the right and above my navel, when I move in a certain way or sitting up from lying, I get this sudden popping, tugging sensation in my abdominal wall. I'm not overly concerned, just curious if anyone else has experienced it. It's not a pleasant sensation but it isn't painful either.

I keep wondering if it might be a hernia - I have no idea what a hernia feels like! This is bub #6 so I wouldn't be surprised at some weakening of the muscle wall.