Birth control

So I just got on birth control about 3 weeks ago and my period lasted 11 days so they gave me this hormone to stop the bleeding for 10 days. Well, it stopped Friday night and I had sex that night and then I had like brown discharge Saturday and Sunday and then started having actual blood Monday night and when I woke up it's back to brown spotting. I still have 4 days left on the hormone but it's not really helping. What do I do??