Ok so today glow says AF is due and I am 12dpo today . Well I just checked my CM and there was a little part that was brown . I haven't seen anything on toilet paper at any time or any when checking CM before today and it was only that one time today that it was seen .  I don't feel like my AF is going to be showing up today and I took a test and it came back negative , do you possibly think it could've been due to implantation ?