My LO is 10 weeks and had been BFing well and we had even got to the stage of her sleeping for 6 hours after last night feed. However we introduced a bottle for last feed and I expressed, she was still fine. Changed this bottle to formula (Hipp) for various reasons. She now takes bottle no prob but then only sleeps for 3-4 hours and seems to have developed really bad wind which wakes her up.
I don't know whether to persevere, change formula or if this is just a growth spurt. In general her feeds have got closer together over the last 2 weeks during the day as well.