Is any of this anything to worry about?

Since the beginning of summer, I have been struggling with health anxiety. I am always constantly worried that every stupid little thing that I feel is something that will ultimately kill me. Ever since I started having this anxiety, I have had this chest pain that really does concern me. It mostly feels like sharp pain that gets worse when I twist a certain way. Every now and then it will be like a feeling of fullness which is what concerns me because I have read that a full feeling in the chest is a symptom of cardiac pain. I went to the doctor over summer and told me the pain was non cardiac and not related to my lungs either. I also had a chest x-ray that was totally normal. I felt better for a while but every now and then, the pain will come back and certainly frighten me. Now just in this past week, I have had both feelings of sharp and fullness that are accompanied by indigestion. (I am not sure if indigestion was present before because that isn't what I was focused on) With this comes a slight labor of breathing. I guess what I am wanting to know is if this really is anything at all to worry about. I am 20 years old, fairly active, and there is pretty much no family history of cardiac problems (except my great grandmother, but she had a heart attack at 93).