Help! My 6 week old, who before yesterday was a good, hungry feeder, has gone all strange! She has gone from feeding for 40+ mins to 10 mins and then fussing. She writhes around and keeps spitting out my nipple, really uninterested. She had a ebm bottle earlier and was the same. It took over an hour but she eventually took 4oz. What is going on?! Her poo is also very green!