One of the real problems with the internet is that average people can contact "Dr. Google" and get scared out of their minds. It's so hard to evaluate the validity of various sources sometimes, especially when you do your research when you're already worried.
If you're saying the radiologist had a concerned look on her face, I doubt it's from the 2 x-rays. I'm sure it was more likely a look of concentration in trying to carefully position the equipment or to carefully evaluate the films. Maybe she was concerned that she couldn't immediately locate the penny. Maybe you just misread the look to begin with - this is not a physician you know well, so you can't assume you know what a particular facial expression means. I don't know - I wasn't there. I just know there are a bunch of reason why this could have occurred.
I had x-rays as a kid before anyone knew that we should wear lead shields. I'm fine. I have dense breasts and fibrocystic breast disease, and I've had annual mammograms. Until 10 years ago, I usually had call-backs and multiple films of each breast, plus extra x-rays associated with breast surgery. I'm no worse for wear due to the x-rays, and I now have clean scans all the time with zero repeats. In my experience, we're at greater risk for NOT having these x-rays. One of my stepdaughters has scoliosis and has had tons of spinal x-rays in connection with multiple insertions and extensions of rods along her spine. The other has a congenital hearing loss and has had tons of diagnostic tests related to that. They've had surgeries and anesthesia. No one has thyroid cancer or any other kind of cancer from
x-rays. In fact, I think our health is better because we've had them.
Do try to relax. I know it's hard but you will find that you actually make better decisions when you don't panic about small doses of radiation or small amounts of anesthesia or small amounts of vaccines, and a whole bunch of other common procedures.