UpDate:

One of the reasons, my primary was suggesting my having MS as a possible culprit for these near fainting spells, is because they more often occurred while taking a shower. Heat and MS aren't supposed to mix.

Since all other things, physical, were ruled out--including the fact that my white blood cell counts are normal, one of the many tests done on my blood during that physical, in late April, MS wasn't quite ruled out.

That being said, since most everyone, who replied here, that has experienced this, stated it was part of their anxiety.

Just started .25 Alprazolam a couple days ago, on Thursday. The conditions in my shower(plus I often worry about the kids while I take a shower, which can also be a trigger factor), were prime for my thinking, OK, here we go, either I am going to have that feeling...or...hey wow...the anti-anxiety medicine, is working!!!

My own personal conclusion. Anxiety was the culprit, and what my doctor gave to me, WORKS!!!