ucler or heart problems

Hi all. I have a very tender upper tummy, bad chest and tummy burning, chest pain, back pain and and I am finding it hard to breathe, well it hurts to breathe as tummy and chest feels tender and hurts when I do, my chest and tummy also feels like I have pressure on it too. I have felt this way for a while now but it's getting worse. Have been to Doctors and they have just sent test off for H pylori as they said I might have that with uclers. Have been to A/E tones of time, a few days ago they done a x-ray, blood tests, E.C.G. Blood tests and x-ray came back ok, E.C.G came back as slight heart block but Dr's say its nothing to worry about. They checked the muscles inb my heart too, all ok. I am scared it ccould be to do with my heart as my sister died when she was 25 of tumor of the heart and they did tones of tests for her even heart scan but they never detected it until she passed away. So do you think it is just tummy problems or could it stil be to do with the heart. Thanks for taking the time to read this. Any help would be great. Tina xx