It depends solely on whether it's changed or not.
You can safely disregard all the other tosh here.
Everybody in the world (adult) generates roughly 125 mms/Hg Mean Pressure within the left ventricle of the heart. They MUST, because this is the mean pressure it takes to push 5 litres of blood round a loop whose total impedance is 0.025, which everybody's is, (-at rest.)
Readings such as you've described are much lower than this and are therefore not only wrong, but totally meaningless by themselves, but if they've recently changed (i.e., suddenly dropped) to those levels then the CHANGE is significant, and you might well be wise to seek advice.
In spite of what you'll read here, (from people who should know better) the 'absolute' readings are not true. That is, they aren't the pressures either within the artery nor those generated at the left ventricle.
It's quite easy to demonstrate this, and to show that the figures your doctor comes up with have more to do with the structural 'strength' of your arteries than the pressure within them.
So your readings are neither "good" nor "bad" ..... they're merely "you" and how you're made, ...tall or short, blonde or ginger, spotty or clear, blue-eyed or brown... it's as simple as that really.
UNLESS THEY'VE CHANGED... Changes are real. Absolute value are not.
And please, don't start taking pills simply because someone in this zoo says you should be -, because "your B/P is too low".. Because (a) the pills won't work but (b) WILL have side-effects. Then your doctor will prescribe more pills, for the side-effects, and so on until one day you'll have the good sense to stop and go back to where you are now. ..
PS. Edit. - Incidentally, just as a matter of fact, "as one gets older the blood pressure gradually rises" isn't true.
What happens is that loss of arterial elasticity simply allows a more true or accurate reading of pressures to be taken at the brachial artery
The originating pressure (ventricular) remains the same in a healthy person (like me!) but actually may well fall away, with cardiac function impairment with age.
Doctors believe these people are healthier but the reverse is the case,
Who said "Truth is stranger than fiction"?