Delayed death from radiation is a nasty way to go.
As for pain from medical radiation treatment:
QUOTE
Horrifying deaths caused by "medical" radiation
For example, Bogdanich reported on the heartbreaking tale of Scott Jerome-Parks who was literally irradiated to death. While he was being treated for tongue cancer, staff in a New York City hospital didn't notice a computer error was directing a linear accelerator to zap Jerome-Parks' brain stem and neck with off-target beams of high-dose radiation on three consecutive days.
He was left deaf, almost blind, burned, and unable to swallow. His teeth fell out among the ulcers lacing his mouth and throat. He died, in excruciating pain, weeks after his radiation "treatment" at the age of 43.
The very day a warning was issued to other hospitals to be more careful with radiation, Bogdanich pointed out in his report, at the State University of New York Downstate Medical Center in Brooklyn a 32-year-old woman with breast cancer was subjected to a huge radiation overdose -- three times the prescribed amount. And it didn't stop there. This intense irradiation of her body went on for 27 days until it burned a hideous, open hole into her chest. The young mother of two young children suffered horrendous pain and then died a month after Jerome-Parks.
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http://conversations.blackvoices.co...x-ray-errors/ec37e65b36754153a7e704bdef17ea65, 22 Apr 2010.
The "burns" suffered by these two people are more of an ionizing radiation induced necrosis of tissue rather than oxidation of the tissues under application of heat. And these were from therapeutic radiation machines, not a diagnosic imaging x-ray. Looking through medical mistake literature; I'm unable to find a single report of a patient reporting a "blow-like sensation" from any radiation device. However, there are numerous reports of patients feeling a burning sensation at the point of aim.
An even better account is of Louis Slotin's death at Los Alamos during the Manhattan project.
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Louis Slotin had been exposed to almost 1,000 rads of radiation, far more than a lethal dose. Kline, who had been three or four feet away from Slotin, received between 90 and 100 rads, while Graves, standing a bit closer, received an estimated 166 rads. A surge of heat "swept over the observers, felt even by those some distance from the source," writes Thomas D. Brock, a retired University of Wisconsin biologist who has done extensive research on early atomic-era accidents at Los Alamos. "In addition to the blue glow and heat, Louis Slotin experienced a sour taste in his mouth [and] an intense burning sensation in his left hand. As soon as Slotin left the building, he vomited, a common reaction from intense radiation." Another commentator suggests that it was as though Slotin had been fully exposed to an exploding atomic bomb at a distance of 4,800 feet.
...
Many volunteers were ready to donate blood for the transfusions doctors deemed necessary. Sadly, all efforts to save Slotin were futile. He died on 30 May after an agonizing sequence of radiation-induced traumas including severe diarrhea and diminished output of urine, swollen hands, erythema (redness) on his body, massive blisters on hands and forearms, paralysis of intestinal activity, gangrene and a total disintegration of bodily functions. It was a simple case of death from radiation, similar to what American scientists and medical personnel saw in Japan among A-bomb victims.
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http://www.atomicheritage.org/index.php?id=92&option=com_content&task=view, 22 April, 2010.
Interesting, but hopefully not applicable in your case is this Wikipedia entry on visibility to the naked eye of X-rays (I can't believe I'm quoting them as a source):
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"Visibility to the human eye
While generally considered invisible to the human eye, in special circumstances X-rays can be visible.[18] Brandes, in an experiment a short time after Röntgen's landmark 1895 paper, reported after dark adaptation and placing his eye close to an X-ray tube, seeing a faint "blue-gray" glow which seemed to originate within the eye itself.[19] Upon hearing this, Röntgen reviewed his record books and found he too had seen the effect. When placing an X-ray tube on the opposite side of a wooden door Röntgen had noted the same blue glow, seeming to emanate from the eye itself, but thought his observations to be spurious because he only saw the effect when he used one type of tube. Later he realized that the tube which had created the effect was the only one powerful enough to make the glow plainly visible and the experiment was thereafter readily repeatable. The knowledge that X-rays are actually faintly visible to the dark-adapted naked eye has largely been forgotten today; this is probably due to the desire not to repeat what would now be seen as a recklessly dangerous and potentially harmful experiment with ionizing radiation. It is not known what exact mechanism in the eye produces the visibility: it could be due to conventional detection (excitation of rhodopsin molecules in the retina), direct excitation of retinal nerve cells, or secondary detection via, for instance, X-ray induction of phosphorescence in the eyeball with conventional retinal detection of the secondarily produced visible light."
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http://en.wikipedia.org/wiki/X-ray, 22 Apr 2010.
