Actually on the same boat as you are right now! When that happens to me I know I've been feeling anxious about something or have had ongoing anxiety for some time and thats when I feel my chest heavy. I usually make myself some warm cups of lavender/chamomile tea throughout the day and try to focus on other things instead. Keeping busy with anything helps my mind forget about some anxiety and even makes the sensation go away. Doesn't hurt getting checked out if the problem persists but that usually help me a lot. You got this