Help!!!!

Dianny

Ladies !!! Back in Feb 11 I took Plan B. According to th app et said I was on day 2 of ovulation, however es now th end of march , and yesterday I started having very very very dark discharge that started a bit but over night filled up a pad, yet today es very light , haven’t even changed my pad all day. By now a test would be positive but they are all negative. Should I see a doctor or maybe dis es a sign of my period coming ?