Hi Scotia,
I had a perineal biopsy in April '22. I didn't need a catheter afterwards. I had poor flow rate too but no retention issues.
The procedure itself was not too bad. I lay back in a raised chair, with my legs raised and supported. They give me a local anaesthetic, and once it has taken effect, they began. I could hear a slight 'click' of the device as they take each sample, and there was sometimes a slight sting, but the anaesthetic dampened any discomfort. At one point, I did get an increase in discomfort, but they noticed me wince and offered more anaesthesia straight away. The procedure probably took about 45 minutes to an hour. When it was finished, they helped me down from the chair, in case I was dizzy after lying back for so long and asked me to wait for about 15 minutes to make sure I was OK. They asked me not to drive home due to the anaesthesia. I found the staff very caring. They chatted to me throughout the procedure, which helped to distract me from any discomfort.
I would do it all again tomorrow if I had to do 😀.
If you are really worried, you could ask for a General Anaesthetic, but this may cause a further delay in having the biopsy.
Take good care of yourself.
JedSee.