Nidge,
Like any other aspect of life the NHS has good and bad staff, and this good and bad staff have good and bad days. In the ideal world you would encounter a good member of staff having a good day and you will leave delighted. But if you get a bad member of staff having their bad day, you will leave not as happy as you could.
I remember one appointment I had where the member of NHS staff informed me in error that my PSA had doubled, he got the decimal point in the wrong place, and when I expressed my concern and alarm, he said "There's no need to jump off a bridge yet".
Oh how I chuckled and immediately felt reassured at his delightful manner. Actually I thought cooking tawt, and wrote a letter of complaint to my GP. My GP then called me and explained the real reading and did reassure me.
If you feel sufficiently aggrieved write in and make a complaint. What is the worst they can do, treat you badly, again? Letters of complaint tend to focus people's minds on the person in front of them, not the NHS patient number.
Good luck.
dave