> So I'm not sure why it is so rare for me to dream, but I suspect low glucose or oxygen may have something to do with it.

You might be having those but “not having dreams” is not an indication of that. And i put the “not having dreams” in quotes because for most people they have dreams but then go on to forget them.

If you are having other symptomps by all means get it checked out. But if your only symptom is not remembering dreams i wouldn’t worry about that.