Light brownish/light pinkish discharge

Fay • Sat, Jan 27

Good morning. I woke up today with a light brownish/ light pinkish discharge. According to the app I am ovulating. But I did start my period late. I was supposed to start on the 11th. But it came the 15th and lasted only about 3.5 days. I’m a usual 6-7 days. Anybody have an idea as to why I’m having this discharge? It’s not a lot. And it’s never happened before.