Hoss - did you stop to consider that he was just checking that you were actually a guy and had the requisite tackle?
(just kidding pal).
As for the finger up the date, a good GP (who can subsequently save your life) should do a prostate examination as a matter of course for adult males over 40 years of age.
My uncle who is in his fifties changed doctors, had an examination and is now being treated for prostate cancer which was diagnosed early due to a thorough medical professional.
Anyway, the guys I associate with probably object to having a finger thrust up your hairy datehole but to checkout your old fella?