What Does Pink And Stringy Vaginal Discharge Indicate?

I started having pink watery stringy discharge 5 days before my period was due. Moderate to sever cramping and breastfeeding and rib pain came with it. Then on the 2nd day of this discharge I started spotting. Then it stopped and now it s just pink liquid. What could this be I m only 20 yrs old I m sexually active. I ve been on the pill faithfully taking it for about 2 yrs. I always use a condom so I don t know what it could be.