Thanks for your question on Healthcare Magic.
I can understand your concern.
In my opinion, we should definitely rule out lung diseases because right sided
chest pain, backache and breathing difficulty are seen with
pneumonia and
bronchitis.
So
consult pulmonologist and get done clinical examination of respiratory system, chest x ray and PFT (Pulmonary Function Test).
Chest x ray is needed to rule out
lung infection. PFT is must for the diagnosis of bronchitis.
You may need antibiotics and inhaled bronchodilators based on reports.
Don't worry, you will be alright with all these.
Your left leg pain is mostly due to nerve compression and it is not related to chest symptoms.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.