My little girl is 27 days and still a lot below birth weight and put on nothing at all this week. She has green poo which hv says can be a sign of not getting enough calories. Hv been today and advised giving 2 formula feeds a day. I have the tommee tipee starter kit and just gave her 2.5 oz (not long after breast feed) and she gulped it down ridiculously quickly. A lot wet down her chin/neck. Her guts have just done a few really Lou's rumbles and a little bit just came out of her nose. I used aptamil from a blue bottle. I'm guessing I should go to sainsburys this afternoon and try and find a slow flow teet (they exist right?)? Any recommendations? Do all tests fit all bottles or do I need to buy new bottles too? Her guts are still going like mad!!!