hi i have been on the pill since august however in the september cycle i was really bad and kept missing it and bleeding on and off however i did not have sex during this time. then in october i was due to start taking it again on a saturday and was away for the weekend and forgot it to bring it with me. so i cant remember whether i took either 3 pills on the monday or 4 on the tuesday. i then had sex with my partner on the thursday and saturday. however it was anal sex and he did not come inside me, but near inside me and im worried some of it may have dripped in. i kept taking my pill as usual and then i finished my 3 week pack on saturday past and it is now wednesday and i have not had my period yet. is there a chance i could be pregnant?