Follow-Up:
I am a 69 year old female and have experienced this five or six times, about a month apart, just as I am about to go to sleep at night. It sounds like an explosion in my head. It is so bizarre I have wondered if I was actually asleep and dreamed it. It happened again last night so I decided to research it on the internet and am delighted to find I am not alone. I don't know what type of a doctor to see for this problem or even if it is necessary. It makes me think that perhaps an anuerysm might be going to happen. Thanks for any input.