So my girlfriend is showing symptoms of pregnancy like nausea, headaches, fatigue mostly and took a pregnancy test a couple days before she was supposed to start her period and it came back negative. Well she is now going on about 3 or 4 days late. The only thing is I'm in the military and preparing to deploy and she is telling me it's stress. Being a guy I don't know all about these things can someone help me a little bit?