Late period, help!

Kate
So according to <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> I'm 3 days late and I took a first response pregnancy test today and it was negative. I've also been doing the vitamin C thing where you take up to 6000 mg a day in order to get your period to come quicker and nothing has happened. Plus I have been sexually active but I can't recall a time my boyfriend ever came inside me or the condom broke. Should I believe the test and my period should come soon or what? I've been stressing out!