Diarrhea for a week, is it normal on pregnancy?

I'm 14weeks pregnant, since my ob change my medicine to ferrous + folic acid, calcium and multivitamins I experience frequent pooping. Like 5-10x a day or kada kumain ako. Almost 1 week na. Sabi ni doc cguro dhil sa ferrous, kaya pinalitan nya meds ko, since 2days ago same pdin.. Anyone experience the same???