Pill AND pregnancy!?

eli

I’m on the pill, I have been for a year and a half now normally I remember to take it everyday, I take it at night before I go to sleep but recently I don’t know why sometimes I have Forgot, I have continued taking it, could this cause pregnancy? I’ve had lower cramping today on one side I am on the progesterone pill only. Sometimes I have break through bleeding but don’t have a monthly period.