All medical doctors have stress especially during your residency period (16 hr workdays). I once considered radiology because it's not a public face-to-face position with the patients, you just read x-rays and relay the info to their doctor. You probably have to hustle to get those reads done quickly tho. Takes a long time to specialize in radiology, 5-6 years after 4 yrs of med school. Get a health care careers book at the library.
If you were asking about becoming a radiology tech (the people who take the x-rays) then run away now!! Repetitive motions cause joint problems and pain, also dealing with some very sick people and positioning them on the x-ray machine. My buddy who trained in this said the tech school brought in hobos to practice x-rays on (i guess county hospital didn't want to pay their x-ray bill)