What Causes Abnormality In The Pap Smear?

My gyno just called to say my pap was abnormal and i have to come in next week to get a biobsy. I was surprised and didnt get ask questions and now they are closed for the day. Im a bit scared now, how likely is it that the abnormality was caused by 1. a yeast infection i had the week before gyno visit and 2. taking plan B the week before my visit? I'm not super worried that i have cancer, but I am scared now that I have HPV since i am sexually active and have had more than 1 sexual partner in my life. I did get the gardasil shot and have never had any std's before...