Hi,
Breastfeeding isn't meant to be a pennance! The good news is that most women can eat pretty much everything and anything they want. A little bit of everything gets passed through the milk to the baby, and a a result, research tells us that BF babies take to solids more easily and enjoy a greater range of foods.
The holiday season can make for an unsettled baby. Often their are family celebrations - lots of car trips, unfamiliar sights and sounds, hot weather, interrupted sleep, people passing her around. and a mum more anxious than usually for baby to be settled and a "good" baby (AKA a sleeping baby) This is all going to take more of a toll on the "settledness" of baby than anything mum eats!
Tell me, is your little one back above birthweight? What is her pattern of waking and sleeping?
Occasionally experience does show that babies are affected by certain foods. Often family history can give us a clue. Does anyone on either side of your families suffer from food allergies of intolerances?
I'd be looking at things other than food you are eating before you began eliminating things from your diet and then doing some detective work re likely intolerances
Warm Regards
Barb