Confused don't know if it's implantation bleeding or the beginning of my period.

My period is due in 6 to 7 days. In my fertile days and on ovulation day I have sex ttc. This morning I got up and use the bathroom I see a small pinkish/ brownish stain in my underwear. When I wipe it's light pink. I'm also 6 to 7 days past ovulation. What u guys think? Do u also think if I take a test now it will show anything if it's implantation bleeding? Or wait couple more days to see if the bleeding stop.