Most variants of The Pill (The Pill is a layman's term applied to a wide range of contraceptive medicines)are based on hormones. since you are using yours to cause and stop period on the day you choose (how nice, you can schedule your menstruation cycle! My the wonders of the modern age) suggests to me that you have a certain amount of hormones in the pill you are taking. These levels of hormones do not just drop completely off 24 hours later, you build up a certain level which remains with you for several days. in some cases several months. Women have reported problems getting pregnant 3 to 6 months after stopping hormone based contraceptives. A single miss does not increase the likely hood of pregnancy significantly. Although the risk is around 2% even with faithful use, the next day miss does not increase it measurably. 2 days of missing will lead to a slight a fraction of a percent) increase - 3 days the increase of risk starts to shoot up 5% 4 days the risks are even higher. The longer the period of time missing, the exponential the risk increases. Given the variables as you laid them out, based upon that data only I would say that the risk is around 2% or not significantly any higher than on your regular cycle of pills. Of course if you really do not want to get pregnant you should use a 1-2-3 punch, the pill PLUS a condom PLUS a spermacide - this still does not give 100% protections, but it reduces the risk of pregnancy to a mere fraction of a percent.