Is Pregnancy Possible While On Loestrin Fe?

Good morning, I have been on Loestrin FE for almost a month now. Is there a possibility that I could get pregnant while on it, I have missed a couple of pills by a hour or a hour and a half. Will it also cause infertility? I am 19, ap. 5'3, and I weigh around 110 pounds. My periods were also irregular before I started birth control.