First of all, birth control pills are not to be confused with emergency contraceptive pills - Birth control pills are to be taken regularly, as prescribed the doctor or manufacturer, while emergency contraceptives are to be taken within 3 days of unprotected sex.
secondly, rubbing his penis against your vagina is NOT enough to cause a pregnancy. For preg to occur, the semen has to be deposited VERY CLOSE to the cervix, which usually occurs with unprotected, penetrative sex.
You need to get more (accurate) information on contraception, the menstrual cycle, concept of fertile days etc. so that you don;t get into an unwanted pregnancy situation or get stressed about a pregnancy every time you get intimate.
all the best!