no af

What is going on with me?

hi there, my last period was on 4/17/2009 and i still have not started, i have several symptoms of pregnancy but all BFN's.
i do know my periods are irregular but nothing like this, is there any reason why my period is so late, im not stressed that i know of, and if i am pregnant why isnt it showing up and what do i say to the doc to have her give me a blood test, she is kinda not wanting to hear it i guess..