So I discovered the source of the problem.
My website programmer had built and customized my new WordPress template within my site but with a slightly different URL extension. Once we decided to go live with the finished product, he took that test version offline and used the redesign. For whatever reason, this new WordPress upgrade brought that early version back into public view (evidently it was never erased, not a good idea), so I had TWO separate sites up, the current one and the original test site, with just slightly different URLs.
The reason the confusion occurred is that the comments needing approval coming into my inbox suddenly started linking to the old site and not the new one. Don’t know why that happened. Bizarre. I now wonder if that test version was never taken down after all.
Thank you for your time! This is the weirdest WordPress situation I have ever come across.