Pink spotting 4 days after period ended

I started my period of the 11th of this month and it lasted 8 days. I spotting light pink discharge almost not even much to notice. It Was very slick feeling. I had sex the night I started my period b4 i noticed any blood. There's no way I could be pregnant right? It has to be something else. My ovulation starts today according to glow and i havent seen any pink since then. So idk whats going on. Im not worried to much just curious about what it is.