Spontaneos pneumathorax in young males is a known occurence. Chest tube
is required only if pneumothorax
is more than 20% otherwise it heals by itself even without any treatment. I think in your case that is what happened. From your description it`s quite clear that you have`nt had any recurrence and you are normal. You should not be smoking
and should do some physical exercise like walking, jogging etc and also deep breathing exercises. You may get a CT Scan
of the chest done to know if you are prone to developing recurrent pneumonothorax . Also get a PFT done to know your lung capacity. If all is normal you will live upto a ripe old age.