I've lost count how many times I've had a rectal exam.
Bear in mind, I was a kid when I first got sick and it just goes to show how sick I was that I really didn't care how many times I got poked.
It only hurt when I was younger, I think because I had a fissure.
Now, I seem to get a rectal whenever I'm in the ER or whenever I get any new doc on my case.
Since I have a perianal fistula, I also get the joy of a rectal and vaginal exam at the same time, but it's never hurt.
Maybe your doc has no finesse.
If it's about being embarassed, well, there's no room for that when you have Crohn's.