It's tough when they are still so little. Did you consider feeding him again? When they wake so often and they are this little, then I usually consider hunger as a possible reason. There is also the 4 mo gs to deal with. Also lots of Los this young will want to cluster feed in the evening and into the early part of the night.
Wrt settling him, I know that lots of moms will try to settle within 20 min and if it doesn't work, to get them up, calm them down and try again. With sleep training, try to be consistent so if you do get him up, do your wind down routine again (eg. Swaddle, story, lullaby, etc) and then do the shh pat and put him down. It may take several days to a week but he will learn the routine. But I found with my dd, no amount of soothing on my part would help if she was hungry.