I am experiencing chest pain or discomfort (quality: feels sharp or stabbing) (severity: severe) (side: left) (time frame: sudden) and fatigue.

Chest pain: You will need to see a doctor licensed in the US for specific diagnosis and advice. You will likely need examination and may need tests such as electrocardiogram. Here is some general patient information on possible causes - and when to seek urgent attention. http://patient.info/health/chest-pain-leaflet

Cardiac chest pain: is rarely sharp. It is more usually dull or squeezing like a toothache. There are many potential causes for sharp chest pain but without an examination and some testing it will be impossible to advise you over the internet. You need to see a health care provider and get checked out.