Ok, being a cuff reactor in and of itself isn’t much of a problem. You can buy a blood pressure monitor yourself and take it on your own if you want to know the real reading. Doctors do it as a quick service but the only way to know what the consistent value is (the important thing) is to take repeated measures over time. The sell them from anywhere from $20 - $100 at drug store chains and they are basically as good these days as any others.
I can’t tell if you are most scared about your blood pressure itself or your reaction to being tested. If it is the former, just buy a home monitor and take it yourself while keeping a log. That is the best way to measure it anyway. If it is the latter, taking it yourself may help you get used to the procedure in a doctor’s office but there is also Cognitive Behavioral Therapy which is good at treating this type of thing. A therapist can give you repeated exposure to the things you are scared of in a non-threatening setting while working out why certain things are triggering your fear.
High blood pressure is not a good thing in general but it generally isn’t that bad in the short-term either. I have chronically borderline high blood pressure just like all people on my father’s side of the family do and they all live a very long time. I have also had incredibly high readings of 220/150 when I was very sick and lived through that too. I get consistent readings that are a little higher than normal even today but I have been poked and imaged by every specialist there is in the last few years and they don’t think that it is something to be especially concerned about.
Just talk to your doctor about it. Mildly high blood pressure readings are like high cholesterol tests. They have a profile that they want to see and, if you deviate from it, they will warn you about it because of the general medical statistics. However, moderately high blood pressure does not generally mean that a 30 something year old man will drop dead next week from it. You can live to a ripe old age with high blood pressure or die early with low. It is a very general diagnostic test with lots of noise that happens to be easy to take and that is why they take it as soon as you walk in. It isn’t a Pass/Fail exam.