Bigbear, hugsss, hang in there, remember my story, my brown spotting was not the AF i thought so yours could be the same too. Monitor, minimize movements and see how. Could be implantation.
And i recommend go for BT earlier to get more supports for pregnancy. KKH like to do day 16 BT which is later than the standard day 14 BT so by right, you can even test already on wed, no need wait till fri.