Hi Jean,
Hope you feel better today, I would suggest if you experience the same headache again to ask your doctor to check your shunt valve. Also take note of your activities prior to the onset of the high pressure headache. By tracking your activities you will learn things to avoid, since most of the time the incidental occurrence of high pressure headaches are caused by stressful activities.
Hoping you will no longer experience that high pressure headache episode soon.
Saleh