I am 29 years old. I did sex with my boyfriend on 17 august. It's was protected we used condom. But it was for the first time so I bleed a little first day and in next day while urinating in morning. My abdomen was paining badly. I was scared of getting pregnant so took one tablet of i-pill, and another after 12 hours and pregnancy test twice, but was negative. My periods were due on 24, but they stared on 23. The issue is I am not bleeding as I used to. Only brown sticky substance is coming very little blood. What's this? Is there any thing to worry about? Really scared what should I do.