Your weight is slightly below expected as per your age and height. Your chest deformity is possibly due to some serious chest infection
like whooping cough
when you were young, I guess. If you had poor growth due to certain vitamin deficiency
can also cause this problem. example rickets.
Your need to have a High Resolution CT
Scan of your chest to rule our certain lung pathology which gives you more tendency to infection whenever you get a cold. Something called bronchiectasis
You also need to get your immune level checked (Ig All types) with some blood test. If these are Ok then you need to check if you have poor absorption in your gut like celiac disease
This chest deformity will be permanent and you need to check, if you have tendency to have chronic carbon dioxide retention (CO2) with the help of a blood test from your wrist (arterial blood
gas). If this become an issue as your grow older you might require a machine which you use while you sleep at night (called BiPAP Machine). This machine help you breath better at sleep to get rid of the CO2 which in your case may remain in your lung due to chest abnormal shape. These are all possibilities and no need to panic.
Just get a good pulmonologist check you out thoroughly. Best wishes.