Shortness of Breath....Help

I am getting myself in a worry thinking I have something wrong with my heart or lungs. I know I am overweight and not fit, but feel out of breath quite easily, its embarrassing because if I am out of breath through walking up stairs or out walking I have trouble getting enough air to then talk and get myself in a panic.
But then sometimes when I am not doing anything I feel the need for more air, and worry I am not taking in enough??
I know shortness of breath is anxiety related but when I feel out of breath I can't help worrying something is wrong?? I have a missed beat which I know about, but thats common I believe.
I have such a fear of something being wrong and the big C word, its just awful x

Petmad,

Fear not, I have exactly the same issue. Shortness of breath is my main anxiety symptom and one I have written about a lot in this forum. Do you feel like you can't fill your lungs fully? Do you feel like your chest is tight, like there is a tight band around it? Does it feel like you're breathing through a straw? I have all these symptoms daily but I can control it now, knowing that it is just the result of my chest muscles tightening because of stress and not because of anything serious. I am slim and quite fit and have never smoked, I have had chest x-ray's a CT scan and an asthma/lung functioning test and everything is normal, proving that this is all because of anxiety. I'm very sure that this is the same for you too.

Its a horrible feeling isn't it, I would be too scared to have all those tests so you are brave. I am feeling stressed as home with the kids, bit hormonal and anxious, and hearing of so many people closeby who have serious illnesses, it makes me feel like I am on borrowed time.
I think its more noticeable when I have done something more strenuous but sometimes it just takes over when I least expect it and then I think, there it is again...I need more air!!!
x