Hi Sammy!!
Like everyone says 'every woman is different' some will experience minor discomfort, a bit of pain, or nothing at all. Don't worry!!
My experience, I too read online forums where women told their horrific stories etc. So I was terrified the day of my appointment. BUT during my appointment I felt ZERO pain and it only took a few minutes. The anticipation/waiting was the worst part. I felt kind of stupid for how worried I was.
Take some Ibprophen 1 hour before the test and you should be fine!! Even if it was a bit painful or uncomfortable it does not last long at all. It takes more time the the radiologist to set up than it does to actually perform the test.
Good luck to you!! Try not to worry yourself too much.