What Causes Pain Radiating From Belly Button To Vagina While Having Endometriosis?

I suffer with severe endometriosis and I ve woken up this morning with a horrible pulling/stabbing pain that goes from my belly button to my vagina. I can hardly move and everytime I stand/sit or move it really hurts. I can t urinate without it hurting and it s crippling pain! I ve been to my GP and she doesn t know what s causing it