Yep, I've had two, and four colonoscopies.
I have what they've called a looping bowel, it loops back on itself while they're trying to get the instrument round, particularly to get a look at the terminal ilium which is where the small bowel joins the large bowel, as I have Crohn's disease and they need to get a good look at that bit.
I now have anaesthetist supported sedation, which isn't a general anaesthetic as that would require the whole theatre malarkey, but is very deep sedation requiring an anaesthetist to administer it, and can be done in the scope suite.
In effect I'm completely knocked out and am not aware of anything or feel any pain. Thankfully.