Looks like you just Oed yesterday, essnce. Fx some sperm from 2 days before made it.
Princess, consudering your recent history of spotting and possible polyp/uterine lining issue, I really would not be concerned by a little brown spotting, especially as your tests are progressing nicely. But I'm sorry it's stressing you out.
I was looking through my past charts, and only 7/12 cycles TTC while swaying have well timed attempts (I.e. no more than 4 days before O and at least 12 hours before O). That includes this month which I consider a fail bc hardly any semen from my early O day attempt made it inside me. Ugh!