Not all spikes and dips are bad, but if you have them first and foremost you need to distinguish between normal and abnormal. Blood pressure fluctuations are extremely common and affect practically every single one of us.
Did you know that erratic circulation, just like everything else, has causes? There is never a coincidence or a heart error that causes spikes and dips. What looks to us as a random change to numbers tends to follow a specific pattern and show up in specific circumstances.
It is NOT true that numbers are steady throughout the day and there should be no ups or downs. Blood pressure fluctuates minute to minute, and sometimes quite substantially. Many fluctuations are only normal, but also healthy. The key is to sift out the good from the bad.
Before however you do that, ensure that your measurements are correct. Machines fail and some are just frank inaccurate. This one is a reliable long-lasting monitor.
Keeping a log and tracing the numbers can be extremely helpful to discover your own heart pattern. I guarantee you, your discoveries will be not only useful, but also surprising. Keep a log of numbers during various situations. The chart below will guide you through the timings.