Does Pre-ejaculatory Fluid Discharge During Intercourse Cause Pregnancy?

Question : hi im wondering if theres a chance that my girlfriend is pregnant. basically we had sex 2 weeks ago (her first time) using a condom and i didnt finish at all, but i know you can still get pregnant from precum. i read that there is no sperm in precum but the sperm that is in the urethra after the last sexual experience, but i didnt do anything for 5 days before we had sex. but she still thinks she might be pregnant. she was supposed to get her period this past weekend but didnt get it yet. she says she never gets her period late, only early. and she also says she always knows when its coming up but doesnt feel like its coming. we took a pregnancy test yesterday and it came out negative. she was relieved for a day but then looked up things and found that false negatives are common. and a different question, if she gets bloodwork for a different medical reason would they see that shes pregnant or would they not test for that. and are minors allowed to ask the doctor not to disclose pregnancy information to their parents? thanks!