Honestly the best thing to do would be have your doctor run a full blood panel including Testosterone and Estrogen levels. Most likely one of those or some other hormone is out of normal. Contrary to what a lot of people think, if you estrogen levels are too low or too high this can cause erection issues. Also the simple fact that over 40% of American males suffer from low Testosterone and don't even know it! The 60% that don't are only medically defined as not suffering from low testosterone, that means many 30 and 40 year old could be producing the testosterone levels of an 80 year old and the doctor will tell them they are fine!