Pink/brown discharge after sex

My period was two days late for the first time I can ever remember and yesterday was my first day of ovulation. I had unprotected sex with my partner last night for the first time since my period ended (Sunday) there wasn’t any pain when we had sex but didn’t use lube and I was on top (I don’t know if that’s important).

I noticed the discharge this morning and it was pink then, but tonight it’s more of a brownish colour, there’s not enough to even wear a liner and I only noticed when I wiped after going to the bathroom. Is this reason for concern?

I googled it because I was afraid it may be implantation bleeding (not trying to conceive yet but not on birth control) and was inundated with stuff about abnormalities in the cervix, I booked in for a pap smear tomorrow but am in Australia and I don’t even know if they are around here anymore- I believe they do HPV tests now, and my last Pap smear was 2 years ago and I’m really confused and stressed now! Someone explain to me some possibilities?!