Help please


I have had faint positives for the last few days (last test in the last hour and faint positive) and due AF on Sunday. I think I O’d late as I had egg white CM on cycle day 17 which indicates ovulation within a day or 2 from this. If I O’d on this day it means today would be 10dpo. I just wiped and had dark brown discharge with stringy bits. Start of AF meaning chemical pregnancy Or is this implantation bleeding? Thank you beauts xxxx