From everything you have said to me you are checking all the right things. Breastmilk is so digestible that often there just isnt that much waste to get rid of ;) So yes, as long as he shows no sign of discomfort , then all is well with him. He will let you know if something is up. If there was a bowel obstruction you would know it by now :)  you are doing all the right things and checking  for all the right things! pat yourself on the back for doing fabulously!