Spotting question

So long story short my husband and I had sex 6 days ago and now I’m spotting, veryyy pink and veryyy light. Never had pink spotting in my life. I’m on the pill but I’m newly on the pill so I know it’s not as effective as if I had been on it for awhile. Unfortunately I’m not tracking my ovulation time so it’s not a big help right now. The other part of this is my Grandfather is dying, he’s been on his death bed since Monday. It’s been a week of little sleep, a lot of care for him and I can hardly keep track of the days anymore. I’m wondering what you ladies think, if this could just be a stress related kind of thing or if it could be an implantation related kind of thing. Thank you for your help 💙