hi. im really worried that i got my gf pregnant. im 21 yrs ol and my gf is 20. we had unprotected sex last dec.17. she told me she was supposed to have her period anytime between dec.24-jan1. she had symptoms of nausea. but on jan 1, she told me she already had her period but it was a lot heavier than normal.like she had to change her pads 3 times that day. she said it was very liquid and bright red. then today(jan 2), she told me her "period" stopped. could she be pregnant? we're becoming paranoid. help please