What Are The Chances Of Pregnancy After Using Protection?

Ive been seeing my girlfriend for 2 months now. 2 weeks ago we had sex for the first time. She was a virgin I was not.. We had sex many times during the night but I only ejaculated inside of her once and I was wearing a condom the entire time. It was a brand new trojan condom that hadn't been stored in heat or cold. She is 6 days late for her period. What are the chances that she is pregnant?