I Had A Scan On 30th Of March Put Me

I had a scan on 30th of march put me at 8 weeks gestation with a edd of 8/11/2016 i had another scan 12th of may which put me at 15 weeks with a edd of 3/11/2016 when would i of likely concieved as i slept with one man on the 30th of january and other 14th of febuary thanku in advance