Newborn tummy rumbles

I have 12 day old twins. My daughter is ebf and my son is bottle fed my breast milk(due to NICU stay). Yesterday, I noticed my daughter's tummy sounds like there is a lot of air moving. She doesn't really have gas though, and it doesn't bother her very often. My son's tummy is doing fine. My daughter is tricky to burp and wasn't able to at every feeding. Since the tummy noises started, I have been sure to get at least one burp every feeding.

I also thought maybe something I ate was causing this, but my son is fine. Could she have a food sensitivity?

My diet has pretty much stayed the same since I had her.