My baby is 6 weeks and I have started transitioning her to formula this week. I am using a Gentle Formula and mixing 1/2 breastmilk 1/2 formula one bottle a day (I travel for work so I cannot keep up with breastfeeding her after I return to work in the next 6 weeks). She has been super fussy this week and I can tell it's because she has a tummy ache; but yesterday she drank her formula bottle at 5pm and was fine and happy until 8 when I breastfeed her. After breastfeeding she was super fussy and then when she got up at 4am I breastfeed again and it took me an hour 1/2 to get her back to sleep because she was acting like her tummy hurt. So I'm thinking it is my breastmilk not the formula that is bothering her?? Any advice?? I feel so bad because I don't know what is bothering her... I think I'm crying more than she is!