Sounds like health anxiety to me. I know coz i recognize your fears coz i have them myself. it's a particularly unique kind of hell living with health anxiety. CBT techniques are super helpful in dealing with this kind of anxiety, much more than meds. I am no expert and i just learned some techniques from a few books and online videos of CBT that ive read and watched. Basic techniques like challenging the thought, its credibility and probability, exposure therapy, thought labeling, and letting the thoughts exist and pass without getting into a fight with them, and a bunch of other methods come in handy while dealing with this, and has helped me keep my sanity intact. Can you learn CBT techniques form a therapist or from books and videos available online..?