precum and pregnancy

well a lot of this information on here has been very helpful but im still worried. my girlfriend and I did it for the first time without a condom and were both 15. i havent ejaculated for atleest 5 days before this happened so i pulled out before i ejaculated and still didnt ejaculate after pulling out. my girlfriend's period should start in about 2 weeks. im still worried about the precum but idk if i should be sinse i dont think there should have been any sperm left over in there sinse it was 5 days sinse the last time. let me know as soon as possible what you think the chances are of her getting pregnant. thanks