My last normal period started on 1 april and ended on 6 or 7th april. My periods are usually regular and last 5-7 days. But I have been experiencing bleeding since 15 april (2 weeks before my period was supposed to start) and its been 11 days and still going on. Bleeding is light, like its on 3rd or 4th day of the period and slightly brownish in colour. There has been no change in my diet or exercise routine. Why is this happening?