Please help, getting worried

Gabrielle • Married my best friend 9-20-14 & mommy to a beautiful little girl ❤️
I know this might be TMI in some cases but I had brownish discharge during ovulation time. I took a cheap pee on a stick test at 18 DPO and it looked negative...I am now 21 DPO and the past two times my husband and I engaged in intercourse I have had light pink spotting right after then it completely disappears. Can anyone help with their experiences/info?