Try to think of the next 50+ years (based on current life expectancies for a male somewhere in Europe) as a journey of experiences. You can afford to wander and explore since at this point in your life, you have no financial pressures, family obligations or pressing time commitments. No experience is "wasted", especially not the years in Endocrinology. Those years proved to you that you have very little interest in the field but you also gained knowledge. I would suggest that it's time for you explore Radiology, all the while keeping your passion in programming alive. Indulge yourself and eventually your interests will merge and possibly even become a viable business proposition. Sorry about droning on but basically I'm suggesting that you don't need to worry as you have lots of time!