Hi there,
Have you tried wrapping him before? Both my boys were wrapped from day dot and loved it even to about 6 months. I found it "contained" them so there was no wriggling etc, but it also made them secure and content. On the other side of it, if you have chosen not to wrap him or he does not like it or wriggled free it may be a step backwards to try/retry IYKWIM. Just a thought for you anyway. I hope for both of you he settles sooner rather than later.