I had an intercourse on the 5th of dec( it was protected and there was no tear or any slip off). I had my last periods on 1st of dec and it is only for 3 days. I have been facing irregular periods for this whole year. And my cycle has gone up to 31 days in this year which has never happened in the past years. It's the 37th day and I still haven't got periods. I have taken a home test three times with the first urine and all are negative. Kinldy tell me if I have conceived.