The pill

So I just recently started taking the pill and I was told to start it on the first day of my period and continue from there. My period lasted the normal 5 days however the past 3 days I'm not bleeding but I'm getting really dark brown discharge. I do normally get brown discharge after my period but this is a lot darker than normal. I'm sorta worried. I'm going to go to my doctor next week to give it some more time to possibly go away but if anyone could shed some light on the situation I would be very appreciative