redroadtraveler - My experience is almost identical to yours, so far. I have had varioous treatments for 18 years (age 81), and just started on Pluvicto - also with no chemo. I am halfway between #1 and #2, and have been approved to continue. I also purchased a geiger counter from Amazon (on sale for about $50) and my findings were the same as yours. So we stay apart for a week or so, just to be safe.
My PSA actually went up from 15 to 21 after the first treatment, but am hopeful that trend will reverse in time. My most serious side effect has been fatigue - but not unbearable.
I will look forward to comparing notes as we travel farther down that road.