A warm welcome to you CelestialFire :)
I'm sorry to hear you're struggling so much with the challenges that can come with anxiety. I believe some people don't fully realise the true impact of certain mental health challenges, which can in turn make things even more challenging. It can definitely leave you feeling lonely in your struggle to better understand yourself.
First of all I should of course mention the importance of getting regular physicals from your GP, to make sure your blood pressure and chemistry are on track. I imagine you're already onto this, having had pressure and blood tests done.
Second, I wonder whether you've considered looking into the challenges that come with being a highly sensitive person (a HSP). One of the most common questions a HSP will ask is 'What am I sensing?' or another way of questioning is 'What's wrong with me?' Of course, an insensitive person doesn't question so much. If someone's fairly insensitive to what people say to them, insensitive to the impact of their own thoughts and insensitive to any subtle changes going on within their own body, there's not too much of an issue for them. On the flip side, if you're sensitive enough to feel the words or nature of another person, feel the impact of your own thoughts and feel any subtle changes that are going on inside you...cue a stack of challenges. To add to this, if you're sensitive to certain stimuli, this can set things off too (such as a sensitivity to certain sounds, visual stimuli such as light, certain tastes, certain smells or touch/feeling of things on your skin).
I used to get silent migraines (migraines without headaches). Before the experts discovered the cause of my symptoms, the symptoms were of great concern to me, as they mimicked a stroke to some degree. Beginning with pressure through my sinuses, things would escalate to loss of function down my left side, difficulty walking, trouble speaking and thinking, my nervous system being triggered and so on. Once it was diagnosed, I was able to say 'I can sense which parts of my brain are impacted by a migraine' - the parts responsible for balance, muscle and nerve function, speech etc). Until then, I had no idea what I was sensing or observing and it was pretty concerning.
Wondering if what you're sensing is a change of blood pressure in your head when exercising, in turn creating certain quirky sensations. If you're seriously worried, you've every right to ask for a brain MRI, just to make sure all's good.