Light spotting?

My period ended on the 21st. We had sex (pull out method) on the 25th In the morning. I'm pretty sure I ovulated either today or yesterday. Yesterday evening and today twice when I wiped I saw a tiny bit of blood (red) and once I wiped with a pinkish tint. What could this be? It wasn't old blood and it was to long after we had sex I think to be from that? It's to early for implantation bleeding so I'm not sure what it could be. Anyone have any idea?