So how much poo? And what's it like? Any history of food allergies or intolerances?
How often is she feeding?
You mention initial sensitivity. Were there any issues with attachment? Was she assessed for tongue/lip ties? Sometimes inefficient latch can result in these sorts of symptoms, also, and be misidentified as reflux.
It's quite common for babies to sleep well in the first 2-3 weeks, and then "wake up" and become unsettled. It might be that there are a few things going on, some normal, some not.
Have you consulted with an LC? It would probably be a lot more helpful than speaking to your average GP.
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