My dd is six weeks old and I still have never felt the "let down" sensation everyone talks about. I asked an LC about it at our first ped visit (when dd was 6 days old) and she said not to worry, that it doesn't start until around 3 weeks. Well, we're at 6 weeks now and still nothing. DD is gaining weight well, so I guess bfing is obviously working well enough--though dd does seem to nurse pretty much non-stop all day long and I'm still experiencing frequent nipple soreness (it hurts a lot when she latches on but does not last the whole nursing session) so I do wonder if there is something we are not getting quite right, though we're doing everything the LC and the books I read have told me to do.