Sorry this turned out to be rather long!
My 12 week old DS is incredibly fidgety when feeding at the moment. He'll come on and off a few times before settling to feed and seems to be taking less per feed than he used to (very hard to judge when BFing I know!). When he doesn't want to feed he REALLY doesn't (screaming until you stop trying to feed and let him get back to whatever he wants to do, at which point he instantly settles. His feeding is much more settled when he's sleepy or if his last feed was some time ago. He's also unsettled when we're out, to the point where he will hardly settle to feed at all and gets upset. I would be more relaxed about this if it wasn't for his weight gain. He has dropped from the 75th to the 25th percentile (was 8lb 8 at birth, was just short of 12lb at his last weigh in two weeks ago) - he is gaining weight steadily but at a slower rate than the charts. He's quite long and getting longer all the time - he's just quite lean. We haven't worried too much about this to date as he has seemed healthy in every other waY. He's very alert and lively, has recently started stretching his feeds out from two to three hours during the day and sleeps well at night. He can drain a breast dry in five minutes when he wants to so I don't think latching is an issue. I'm possibly pushing him too much to feed more frequently, partly because of anxiety over his weight and partly because he was every-two-hours-like-clockwork for the first nine or ten weeks of his life. I also have fast let down and very small breasts, so I tend to feed him stomach-to-stomach with him on his side, or even leaning back with him lying across me.
Any advice would be great. I had a hard time getting BFing established so amen't terribly confident.