Spotting HELP URGENT

Ma

So my period was two weeks ago and my next period is next week. But Friday I start spotting brown and light pink and now when I just whipe it’s pink? What does this mean? I have no  nausea or anything like that. I took three pregnancies text two Friday night and one Saturday morning came back negative. Also I’m on birth control this has never happened to me any idea why this is happening? I’ve been on this pill for 1 year two months.