Confused!!!!!!

3 days of pink spotting only when i wipe im in cd16, 12 days after the last day of my period... but no positive opks, they are not even getting darker they are super light for the last 9-10 days(I do them twice a days just in case) No cramps (I always have bad cramps before and during ovulation) and my last period was lighter and shorter than usual 🤦‍♀️ what could it be?