campbell's soups are notorious high in sodium. for the general population this is not necessarily a good thing. especially if you are mayor michael bloomberg who is a jihadist against sodium.
if you are a severe AF person, campbell's soups are just what the doctor ordered. consider a variety of other high sodium foods too.
find something crunchy that your body likes, corn chips, potato chips, fancy vegetable chips. preferably one of the organic brands that are baked or use a good quality oil. get some good salt like himalayan rock salt or celtic salt. and salt your chips heavily, this is likely to help you too.
some AF people will dump too much sodium due to aldosterone imbalance. snacking on salty things helps a lot, especially in the a.m.
licorice root must be of high quality and a potent extract. the very dark ones or ones that look like thick black tar are usually potent. the regular teas aren't likely do help much.
there is an ayurvedic remedy called chyawanprash which is specifically indicated for cases of long term exhaustion.
i would recommend also for you the budwig flax oil/cottage cheese recipe. between that, salty foods, and a good licorice you would probably be feeling a lot better in short order.
running in polluted environments is not necessarily a good thing to do either.
asthma is (partial) detoxification of the lungs, so you probably have accumulated a lot of chemicals/metals. you want to support this detoxification and allow the body to expel these contaminants. avoid all dairy products. steam saunas, salted lemonade and hot compresses may help things palliatively. if you get a productive sputum or cough, you are on the right path.
i think you said you were of slight and thin build. in ayurveda this indicates that you are of vata constitution (prakriti). not coincidentally, the ayurvedic recommendation to balance vata is salt and oil. so no surprises once again that salty soup makes you feel better. vatas do well with warm climate, salty, oily foods. antagonistic to vata are dry, cold foods, windy cold climates, irregular eating habits. please do some more research into your body type and you will likely find some relief.
some vata specific foods are sesame oil/tahini, molasses, papaya for constipation, the herb 'hing', spicy foods in general, chai tea, dates. avoid most beans unless soaked and cooked butter soft. warm salty soup is probably one of the best things for vata imbalance.