Hi pj,
Nothing at all to worry about, honestly. I had one two years ago when I fractured a bone in my thumb/wrist. I was called into the X-ray room, asked to put a special vest thingy on to protect from any radiation. The radiographer placed my hand on an X-ray table, went behind the screen and took some X-rays. Totally painless and over in seconds.
I know how you feel with anxiety and getting worked up about things but honestly it's nothing to worry about.
Take care xx