I had my period nov. 3rd and I had it for 5 days. So nov. 8th it was done. But then since nov. 8th I have had this dark brown almost black discharge for 18 days. I heard of implantation bleeding but I haven't had sex this month. I have been with one person when having sex. So it can not be a disease. Also I heard that implantation bleeding only lasts for 2 to 3 days max. Im extremely confused and I don't think I could be pregnant if I had my period already. This is scaring me.