Nutramigen and fussiness

Hello moms! My almost 7 week old has been very fussy in the evening times from 9 to almost 1 o’clock in the morning. We started Nutramigen on Monday by doctors orders since she has a milk protein intolerance. But we’re still seeing the fussiness. Is this normal? Does anyone know when it’s supposed to fully work? I’m feeling a bit hopeless 😞