BC Pill...

So I am on BC pills, I've been on it for 10 months, no I am not on it like I should be, I usually miss a day and double up the next day or I'm hours late on it, my mom is the one who wakes me up to take it before she leaves to work, but sometimes she just be forgetting and won't wake me to take it, I see my boyfriend pretty much everyday or he sleeps over, and we have sex the majority of the time, yes he cums in me, would just like to know if the pill is really that effective, or if I can get pregnant right away if I take it late or miss the pill and have sex the same day.....??