Welcome to EmpowHER.
A blood pressure reading lower than 90 millimeters of mercury (mm Hg) for the top number (systolic) or 60 mm Hg for the bottom number (diastolic) is generally considered low blood pressure.
Low blood pressure might seem desirable, and for some people, it causes no problems. However, for many people, abnormally low blood pressure (hypotension) can cause dizziness and fainting. In severe cases, low blood pressure can be life-threatening.
The causes of low blood pressure can range from dehydration to serious medical or surgical disorders. It's important to find out what's causing your low blood pressure so that it can be treated.
As to why your bp is hard to hear/find - we cannot say. Your doctors office staff may not be taking it properly. Ask your doctor about this.