Brown discharge all week

I’ve been having dark brown discharge all week long. I’ve been taking the birth control pill for more than 3 months and recently the time changed so technically its like I took the pill an hour earlier than usual. So maybe it’s because of that? Also I had unprotected sex about 3 days ago, the day after I had a small amount of blood when I wiped but now it’s just all brown. And I’m not suppose to start my period until about 5 days. Any ideas of what it might be?