In theory frequent exposure to even low doses could add up to a cancer risk,as it is the cumulative effects of radiation that would normally concern the patient.
So your question cannot be answered unless the degree of the suspected excess radiation (due to the machine's breakdown) is known.
Chances are that it is more of a psychologically induced symptom than
the actual radiation exposure.
Even in developing countries, this is old technology and one would expect that something as basic but also critical as this, would be thoroughly checked, before exposing patients to unnecessary increased radiation.
Look into Wakame miso soup.
Wakame is a seaweed that has been shown to help reduce radiation damage.
After the nuclear reactor disaster in Japan, I contacted my 3 former japanese exchange students and ALL of them had followed the recommendation to increase their consumption of this miso soup, to
minimize the effects of radiation exposure.
You may want to do some research on this.
I read some relevant studies at the time, but I did not book mark them.
I hope this helps.
You should book an appointment to see your doctor to listen to your chest.
It may be just coincidental about having the xray done and the chest pain; could be psychological like TheLightSeeker mentions.
As you are feeling pain when you take a breath, you may have had too much pressure on your chest and this is a muscular thing or it may be an infection like pleurisy.
I would presume the xray would show this up.
Where you told the results straight away, or told to see your doctor for the results?
Book an appointment and speak with your doctor.