What Causes Vomiting And Delayed Period After Taking Unwanted-72 Followed By Sex?

Hi...my gf didn t have periods for whole Feb month neither she had any physical contact before that..I met her on 28 Feb and had an unwanted sex but took unwanted 72 within 1 hour after having sex..she felt like vomiting... and mood changes after having pill...what are the chances of pregnancy and delay in periods??