Brown discharge all day then aunt flow came that night.

What happened? I was only 2 days later than usual. Cycles usually 25 days. So I woke up that morning. No aunt flow. Later that afternoon a small amount of very brown discharge started spotting. This happened without change in color for about 8 or more hours. Finally that night it started turning pinkish red. And the next morning it was a full blown period. I've only ever experienced brown discharge right when my period ends. Also this cycle I noticed yesterday there were several small clots when I would wipe. Usually a couple I only see. Curious if anyone has any idea what's happening. Can't go to doctors until March 1st.