My Period Date Was Around 6th And I Haven’t Got

My period date was around 6th and I haven’t got my periods. But I’ve been getting a drop of brown blood randomly since 2 weeks and specially after I’m working out . I have cramps and backache also but no sign of period. Also 3 weeks back I had unprotected sex but there was no ejaculation inside and 2-3 days back I took a test and it came negative.