hi i been on birth control for years, i am on the 21 pills pack i take it from the last day of my period for 21 days and my pill free week does be the week of my period, i don't always take it right some months i just miss a pill a day but take it early the next day when i remember....i take it at half 9pm to 10pm every night, but 4 days ago i forgot and had sex i took it at 3am that night after the sex, we used protection but the condom always slips, it do not slip off inside me it slips to the top of his penis and he just pulls it back up and we continue.....my period is due in 5 days, i usually get sick days before but this time i feel really different like i want to just throw up throughout the day and night, do you think i can be pregnant from what i said?? have i been taking my birth control right for the past years?? am i suppose to take pills during my period??