Is Pregnancy After Unprotected Sex Possible While On Kariva?

I take Kariva Birth Control every morning. The time I take it varies by about 3 1/2 to 4 hours depending on the day. I make sure I take it every day and have not missed a pill this month. I just finished my last white pill yesterday (8/9/10) and had unprotected sex, meaning no condom, around 12:30 AM this morning (8/10/10). I started on my first of two green pills today and my period is to show up on Thursday (8/12/10). Should I take the morning after pill, as an extra precaution, or am I fine. Again, I didn't miss any pills this month, but if I do I always double up the next day.