Why?!?!?! AF and EWCM

Just when I think I am getting the hang of TTC and know what to expect month after month... I get egg white, super stretchy CM, something I would have loved to have seen 14 days ago. But now I have a really light AF that started at 10 DPO. It has been so light, I don't even "need" a liner or pad. So thinking I should have hit my heavy day already, I decide to test, just in case this is implantation bleeding. Well that would obviously be when I get an evap on 3 different tests. So frustrated, so disappointed... Anyone ever experience AF and EWCM?