The interleaving of external and internal observation made this a very interesting read! Thank you for writing this.
I had something similar happen to me to: First, a feeling of doom and a strong headache on the left side of my head. Then a tickling sensation in my right hand, then numbness. Then, within minutes, I lost my words.
I could still think normally - for example I reasoned that it made sense that my right body side was affected since the left side of the brain, where the language area was located, controlled it. So everything else felt and functioned normal. When I found words and wanted to speak them, they were often switched up.
The human brain is fascinating. Have a look at this:
The last test before my lobeectomy was a SEEG surgery. (I had 11 electrodes 3"+ long shoved directly into my grey and white matter) The last part of the test is stimulation. They're applying stimulation at different voltages, amperage and frequencies to very specifically triangulated ares to be sure there aren't any cognitive, motor neural or autonomous functions in the parts they want to resect. I had to describe what I was seeing, feeling or hearing for each stimulation. It was absolutely bizarre. For instance, during one of the settings I had no muscle tone and struggled to lift my arm to point at the TV, another I had an increasing frequency sweep from one ear to the other. It was neat-o.