What Causes Vaginal Spotting And Nausea After Taking Plan B Pill?

my girlfriend and i "had sex" on what she said was her ovulation day. it was more of i went in for about two minutes without a condom and didnt finish or anything. she is not on birth control so just to be safe i went and got plan b one step. i know there was different side affects that come with it. right now she is feeling sick, headaches, red spotting/discharge. we took the pill about six days ago which was within about fourteen hours of when we had sex. is there a reason why i should be worried that she might be pregant or is this all just from the pill?