I had one about a year ago. I was worried before hand but it wasn't as bad as anticipated.
I drove myself there and back which was the hardest part as was in a different town ;)
All staff very professional and understanding of how embarrassing a procedure it could feel.
First nurse took me into a private room (bed and toilet) for the fleet enema. Left me in there to let it work and then use the toilet.
Dressed in a gown (had to bring in own dressing gown from home) waited in a sex segregated waiting area.
The procedure itself was ok. Quite a narrow tube. You get to watch the screen so can see inside your own bowel.
The staff kept me chatting to distract from any discomfort. Not painful but just felt a bit pushy as it got higher up. But then it was all over and removed tube.
I was then wheeled to recovery for a few minutes rest before getting dressed and leaving.
One thing I will say is be prepared for wind! ! They pump a bit of air in to get better view. I felt a little crampy throughout thw afternoon and then fine.
Good luck op. Try not to worry too much. It truly isn't as bad as you might anticipate.