If I only have taken two of my white pills will i start my period.?

I'm on Yasmin. I start my period on the fourth day of the white pills. I have been on it for 2 months. In my 2nd month of taking Yasmin the time changed and it messed my schedule up big time. and also should I worry about getting pregnant if I did it a week before I was to start my white pills and I also forgot my pill for one of the days the same day we did it.