Lung Collapse after lung resection??

Hi I just had lung resection 1.5 months ago, y is a person who had undergone lung surgery more susceptible to lung collapse???!

and the lung drainage tube scar, is extending inwards, and is ugly!! is there any way i can do to make it flat?????????????????? (other than cosmetic surgery) how to make it heal nicer?

and i feel pain at the lung drainage tube area.... y is that so.....