Several things come to mind which may lead you in the right direction. Getting an MRI is a good idea as worsening headache over 40 along with your other symptoms and family history (sometimes AVMs run in the family) - its encouraging that it is negative. The one white spot is probably incidental, although I have not seen the MRI and cannot confirm this.
One is are you getting enough sleep - sleep deprivation could easily cause the above symptoms, do you have symptoms of sleep apnea - snoring, biref periods of cessation of breathing at night leading to tiredness during the day. Crystal in the ears refers to otolith disease - an inner problem that produces positional vertigo and nausea, diagnosable by neurological inner ear testing. Migraine (previous headaches may have been milder migraines unrecognised?) can cause nausea, headache, and can be triggered by certain stimuli ?odors in the car, foods, weather. Blurry vision while driving at night can mean a loss of peripheral vision - have your eyes checked out by an eye doctor and be evaluated for benign intracranial hypertension. Avoid caffeine and alcohol.
A neurologist can check for all of the above possiblities and would be a useful consultation
Normally I wouldn't post a comment before the doctor offers his/her thoughts, but I wanted to mention that my mother has had the same symptoms, except that it's happened not only while driving. Her dizzy spells were caused by a diabetes medication (prescribed to protect her liver) that caused her blood pressure to drop too low. After the doctor reduced that dosage, the dizzy spells stopped. I bring up diabetes because you mentioned a history of stroke in your family, and diabetes can be a big factor. My mom had also had carotid artery surgery to remove a partial blockage. They insist the blockage wasn't related to the dizzy spells but I mention it anyway because the surgery was done around this same time. Could be coincidental but the doctors do believe it was because of low blood pressure.
My uncle (not her blood brother) has also had 2 similar spells. He actually fell out of his chair but he gets to the point where he's barely responsive (we called 911 the first time because we thought he was having a stroke). He's also diabetic and takes the same liver protection, and coincidentally, has also had carotid surgery. It's too soon to know if the same medication was the reason (they JUST reduced it).
Diabetes was ruled out by bloodwork. I'm not on any medication, except for Hormone Replacment that I have taken for years. My Blood Pressure is in the normal range. Thanks for your suggestions.
Next time you have bloodwork, you might want to check for B12 deficiency.
Thank God, I'm not crazy. The exact same thing has happened to me a few times in the last two weeks. Each time, I'm driving at least 65 miles per hour. It's always in the morning. And it starts with my feeling a little dizzy, then my vision starts narrowing, my hands start feeling cold and clammy, and I start feeling extremely disoriented. Each and every time, I've managed to get my car off the road, fortunately, and it takes me several minutes to clear my head enough to drive again. I'm 40 years old and take thyroid medication and Wellbutrin. I've also been getting dizzy spells when I'm standing and talking to someone, usually when I'm trying to focus on their face while they're talking. When these "spells" occur, it feels like my brain is a snow globe that's just been shaken. But I had an MRI about two months ago and everything checked out okay. If anyone has any idea what this might be, I'd welcome it!
I have had the same feeling that you describe, I really understood the part where you said, "I've also been getting dizzy spells when I'm standing and talking to someone, usually when I'm trying to focus on their face while they're talking". It is weird how things begin to get disoriented, it's like I have to focus to just stay awake and it feels like my brain is going to shutdown. I too had an mri/mra a couple of months ago which turned out fine, lots of blood tests good (just had two more yesterday, to check out thyroid & b12), went to neurologist yesterday - I will have an EEG next week to see if it might be seizure related (he is guessing that results will be fine). Couple of things he mentioned were a possible migraine or my symptoms possibly related to anxiety.
It is scary though... last weekend I was at a football game standing most of the game until the 4th quarter when I just had to sit down for the rest of game, it felt like I was going to faint or my brain was about ready to shut down (I started getting more nervous/rattled as I was watching the action and things were becoming less clear). After the game I had blood pressure checked which was fine and my blood sugar level was good. Felt drained afterwards and for the last few days have felt somewhat drained & a bit "foggy" too, kind of beginning to get afraid of social situations since I'm worried things will get cloudy. Anyways I've rambled enough, feel better though.