Pregnant?

I have been tracking my cycles since September. Before then, they seemed to be pretty regular. I started trying to conceive this month, which is almost over, and for the first time I'm late... super late. Af doesn't look like she's gonna die up this month at all. I've had two negative tests, a few pregnancy symptoms and no sign of af. How long should I wait before I test again? I should have started on the 25. I am now on cycle day 36.