How to take birth control pills for the first time

Hello, I started my birth control pills (GIANDA) on the first day of my period; as prescribed by my gynecologist. My menstruation lasts 5 days, I started my pills on 04/02 and after my corresponding 5 days it still continues to go down, it is not much, just a few brown spots, but when cleaning me there is clear bleeding, but today is 04/09 and I continue to stain in this way.

Why does this happen? It is normal? Should I be worry?