Posting for a friend, I'm out of advice!
Friend's 4 week old has been fussing, latching on and off and crying lots and lots at the boob all evening for the last few days. He won't settle anywhere but on her, and even on her he's not very settled.
Feeds well and sleeps fairly well in the day, this is just an evening thing. Only the last few nights too I think.
I suggested maybe over or under supply, or fast or slow flow. Or gums, wind or reflux. Then I ran out of ideas!
She thinks probably not oversupply but how do you tell which of the others it is? Or if its something else?
If 'just' a growth spurt, cluster feeding etc then how long will it last until he calms down and gives her an evening off?