What would you think this is.....?

sounds like she may be a bit colic. I found out that my baby girl had colic, and I never would have thought about it because she wasn't a crier, just very very fussy. She would also stop fussing in the upright position or on her belly. Being on the belly helps take the pressure off the gas cramps they get with colic. Mine was exactly the same way and she did not have reflux. Common with reflux is crying during feedings and excessive vomiting.