Switching formula

Ashleigh • Mommy to a beautiful babygirl my 🌈..*1/9/18👼🏻*1/23/20👼🏻👼🏻*

My lo is 2 weeks old she was originally on similac pro advance since the hospital but 2 days ago the doc said she has acid reflux and was told to use enfamil ar is it normal for her to have diarrhea from changing formulas? Does she just need to get use to it?