Me and my gf had sex on 18th DEC. We used condoms. But after that she got period on 5 the or 6th of Jan which was her normal date. But it lasted for only one day which happened for the first time in her life. Usually she used to have 4-5 days of period. From yesterday also she is having some vaginal discharge. So are these indications that she is pregnant? What are the ways to confirm it?