Duckie had gerd, though she seldom actually spit up. I got into a huge argument with the pediatrician over that but he finally relented and gave Duckie the test at six weeks, three days. My poor baby girl suffered in great pain for the first eight weeks of her life. She was incredibly fussy and remained fussy even during and after treatment was discontinued. She couldn't sleep well either and was exhausted, I think. Her startle reflex never really calmed down and, we found out much later, she was exhausted from nursing because she has a slight tongue tie.
I'd check these things out: GERD/infant reflux, tongue tie and watch for signs of sensory integration problems as she gets older.