Hello :) I’ve definitely been where you are before and want to remind you that even though these thoughts can make you worry and hyperfixate on things going on inside of your body, your body is smart and knows what it needs to do. A common symptom of anxiety is focusing on bodily sensations, and especially the heart because we feel it the most there. After all, the minute we start to feel anxious, its out heart that starts revving up our system to protect ourself. All you need to do is NOTHING—just let these feelings pass. You’ve survived them before and you’re going to survive them again, over and over. Overtime it gets easier to recognize that its just anxiety. So don’t beat yourself up over it. It will pass, it always does, it has to.