You have history of chest infection
and it was treated with Augmentin
But if you still have chest pain
and piercing upper back pain- there are chances that infection is not yet cleared up completely.
May be infection is present in pleura i.e layer over the lung. If your chest pain increases on coughing, it also indicates pleuritis
Check with your treating physician, doctor will find out if its pleuritis or underlying chest infection with X-ray and clinical examination.