negative blood test but still pregnant? anyone?

Sassy
I'm on CD 50, no period and what I thought were very faint hpt's.
Had a blood test done yesterday morning and got the results today. Negative. Hcg level was less than one, apparently. 
Has anyone had this happen to them but went on to find out they actually were pregnant? I have plenty if not all of the symptoms. No signs of period anytime soon..