Hi,
tamuprof has had personal experience with this type of anxiety and has excellent advice. White coat hypertension is also the main reason most BP measurements taken in a doctor's office are inaccurate.
When you take your blood pressure using a home (oscillometric) monitor, this is usually what happens:
the cuff around your arm inflates to a pressure ABOVE the systolic pressure in your brachial artery. At this point the blood flow is zero. The cuff pressure is then reduced to a level below diastolic over thirty seconds. It is at these times (zero blood flow or below diastolic level) that the cuff pressure is practically constant. When the blood flow is present and restricted - anything in between the two points- the cuff pressure varies. These variations are picked up by a sensor. The blood pressure values are then calculated and displayed on the screen of the monitor. The end result you see on your monitor is a calculation, not an actual measurement.
It is also possible you somehow hear the turbulence and vibrations of the blood flow as it rushes through your compressed arterial walls when the blood flow is restricted.
Some of the home monitors are not equipped to produce accurate blood pressure measurements in people with certain heart and circulation irregularities. Others are capable of measuring blood pressure in these people correctly.
Listen to the other posters - things will get better.