Over the past ten years I have become extremely conscious of my testicles, particularly my left testicle on a regular basis why is this?

Also more recently I've become extremely aware of my heart and sometimes it feels tight and other times I can sense it consciously like palpitations, but it isn't beating unusually or dysfunctionally. There is nothing physically wrong with my heart as indicated by ekg, stress test, or echo, so what is the reasoning for this?