Charlotte is doing exactly the same thing....its been going on for a week now, but shes also been vomitting up every feed....so i took her to the Dr cos my CHN was "too busy" for 3 days...grr..ANYWAY! lol Took her to the dr and he sugested that it may just have somethine to do with my let down reflex...
Its REALLY REALLY strong...and she often has trouble dealing with it, so he said some postural feeding.
He also suggested that she may just not need to feed as much and she would be getting more each feed in the same length of time....Does that make sense??
So been doing all this and she seems to be coming out of it - havent had massive vomit for 2 days now!

Hang in there and try to stay calm Good luck chook!