No period, but ALLL Negative Tests...

So I'm officially 7 days late for my period, took three urine tests during this time, all solidly negative, and then called the Dr's office today for a blood test because I had an ectopic a few months ago and was worried it was maybe just low hcg and not showing up on the urine tests, but that was negative too. So now I'm just hanging out till my appointment next Wednesday wondering if I'm ever going to get a period and why I don't have one. I've always been super regular, even after having an ectopic pregnancy, my body jumped right back into a normal cycle length. This is so strange and so confusing.