Any of you ever experience suddenly getting an implantation/estrogen dip after previously having constantly high temps after ovulation, and not being pregnant?

I never used to have estrogen dips, but last cycle I did, followed by a really weird period. Spotting for 3 days, then really light period, all brown, not red, and then another 3 days of spotting. Since then I've also had headaches and more than usual discharge, which were my symptoms last time I was pregnant as well, but last time I also had really sore breasts, and now I don't.

I am trying not to think anything of it, but it's difficult... I figure as long as I have no definite symptoms I'm not gonna waste a test, and keep charting as normal.