Vvfl 12dpo (bfp) then no line or much much lighter line 14dpo.

12dpo I posted here with my vvfl and we all agreed it was a BFP. 13dpo I tested again, the line was still there but it wasnt any darker. Today, 14dpo (day AF is supposed to come), I tested again and I almost cant see the line. Ive had some menstrual kind of pains for a few days. Took my bbt today and It was 0.10 lower. Not below coverline but still, a little lower. Has this happened to any of you before and ended up with a positive outcome? I feel sort of hopeless now, I still have some cramps but I just dont feel pregnant anymore (i had a miscarriage in january so Ive been pregnant before). The good thing is that I had a blood test done yesterday so I will know my hcg levels as of yesterday. If I end up not being pregnant I think I wont test early again 😐