I can't diagnose you and I have no knowledge of any possible physical ailment you might have, so take what I say with a grain of salt. But I thought for most of my life that I didn't have anxiety. I even got diagnosed with anxiety by my psychologist that I was seeing about my depression and I didn't believe it until a few years later. I was under the impression that anxiety was people who walk into a room and immediately find every possible exit and plan their escape in case something terrible happened. Or someone who just randomly gets panic attacks for no reason. Or someone who can't stick their hand in a lake in case something pulls them under. While these things are definitely signs of anxiety, anxiety can't be put into a box. It manifests in different ways for every person. I don't do any of the things I named and I've never in my life had a panic attack. But I won't buy a shirt if it seems "too red" and if I hear someone laughing I assume it's at me and every time my parents visit me, I have to tell them to drive safe on their way home because if they died after visiting me, I would blame myself. But my experience is also not the definition of anxiety. If you are wondering if you have anxiety, I would advise you to do your research and read about other people's experiences so you can notice potential patterns in your life. And think about the situations you're in and what you're feeling emotionally when you have a heart palpitation.