I was on orthotri-cylen lo and I missed three white pills starting on May 13th. Five days later I was bleeding for about three days and I'm not sure if it was because of the pills or if I could be pregnant. The last time I had a sexual encounter was on April 11th and I did get I hope was a normal period and I took a test and it was negative. I have stopped taking the pills because I wasn't sure when to start back taking them