I think you might want to make sure you're burping him well after each feed to make sure that it's not part of the issue. I found it really hard to get proper burps out of mine when they were that tiny - required lots of lots of patting and rubbing, but they would settle so much better once they got the air out. It seemed for your other post that he seems to have his days and nights a bit mixed up - is he awake and unhappy, or just awake? My third was like that -- he would sleep peacefully during the day but once night rolled around he just wanted to be up and awake.