Is that the only clue you have at this point, that you had sex after your April period with two guys one day apart, and then in May you realized you were pregnant? Could you give some dates? First day of last period, usual length of menstrual months (how often the next period usually comes), whether or not this is a regular number of days or your period comes irregularly month by month, when in the month since your last period came you had sex with guy 1, and then when you had sex with guy 2? I'm trying to work out if you might have gotten pregnant earlier than in the time period with both guys.