Took viagra, had sex. Holy crap, a horrible headache at orgasm. Out of the blue, sudden and a 9 out of 10 on the pain scale. Had to tilt my head down to relieve a bit of the pain. Occipital, base of skull, does not seem to be muscles as movement is not restricted and does not create pain. Maybe spinal?
I don't get headaches and this is the first time I've ever experienced anything like this.