So I am currently 2 days late for AF I was able to pinpoint when I ovulated which was about 14 days into my cycle. My SO and I had sex within my fertile window. The following Saturday I had uncomfortable back pain and slight cramping. That night I wiped and had some light pink on my toilet paper. That was about 9 days ago which will make me 18 dpo and I'm still getting BFN. Ive checked my CM which is clear and my cervix is high and soft. I've been really tired and past two days I've felt so slight pain down there not period cramps but different and past 2 nights around 6pm I've felt a little naseous. Any advice???