Needle in a haystack

I lead an active life and typically feel well, but in May of 2021 after a few weeks of fatigue and just overall lack of energy coupled with occasional lightheadedness I decided to call My physician,Dr Richard Martin. After a considerably detailed interview with Dr Martin, he suggested I get some rest and we would do one test to check a couple things. I generally felt okay other than the fatigue, and from what I recall my vital signs were normal. Before leaving the office I stopped and got the CT scan he requested. By the time I got home Dr Martin had called to inform me he was calling in a prescription and that I had developed pulmonary emboli. I'll never know how serious it was or how close I was to having a catastrophic event ? Fortunately for me that event never happened. I don't understand what prompted Dr Martin to order the test he ordered for an otherwise healthy individual? Additionally, he and his office staff were incredibly helpful after the diagnosis in dealing with the anxiety that arose after the diagnosis. Dr Martin was thoughtful and understood what I needed to hear to help me recover. I feel very fortunate to have a thoughtful physician like Dr Richard Martin. I hope everyone could be so lucky.