Hello Dr,if Someone Had Unprotected Sex On 3rd And Decided

Hello Dr,if someone had unprotected sex on 3rd and decided to take both the two p2 on Friday midday will the p2 still work? And also if the same person had unprotected sex today with a different person whom she suspect is sick is she suppose to take p2 again and what should the person do so that incase this guy is hiv positive she doesn't get infected?