As I grew up and became a medical student and then a medical doctor, I realized these must be what I'd suffered from as a child since I saw the same symptoms as I had. These days though, we have more specialists and more diagnostic tools and it makes diagnosing easier. I learnt that the x-rays needed for the diagnosis of URTIs especially sinusitis and tonsilitis aren't just chest x-rays but also x-rays of the postnasal space and the paranasal sinuses.
X-rays are a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays.
X-rays have numerous uses, medical and others, for example it can be used for airport security. In medicine, it has both diagnostic (x-rays, mammography, CT scans, e.t.c.) and therapeutic (radiotherapy) uses. Be careful though, they can also be harmful as they cause cancers as they have been classified as carcinogen. Before a pregnant women does an x-ray, the benefits or the x-ray should be weigh against its risks. For further reading, go here.
Have you ever had an x-ray or any other form of radiological procedure done before?