How Low Is Too Low For Blood Pressure For Someone Who Is Almost 70 years Old?

I went to Sam’s Club today to pickup a rotisserie chicken and some other things for lunch. Decided to sit down and get my BP checked at the machine next to the pharmacy area. It was 82/50. And marked as “normal”. Just a couple months ago my primary care doctor wanted to put me on blood pressure meds but I decided to stop drinking coffee and my BP came down.