What kind of bleeding is this?

Hello, I had sex almost 4 weeks ago as of tomorrow on the last day of my period with a condom and the pill and yesterday I started to bleed brown and it had random small clots. Ever since I started birth control sometimes I don’t bleed so heavily that it gets onto a pad. I’m supposed to start my period anywhere from the 14-15. Please comment if you have an idea. I know it’s very difficult to get pregnant with the use of double contraceptives but I just wanted to see what other think.