please help me, this is my BBT chart, my period was 5 days late, I had a brown spotting for 2 days, yesterday and today it is already creamy white. I did a test yesterday, it's negative. What does it mean?

please help me, this is my BBT chart, my period was 5 days late, I had a brown spotting for 2 days, yesterday and today it is already creamy white. I did a test yesterday, it's negative. What does it mean?