Severe lower left abdo pain for 2 weeks, spreads across whole lower tummy, feel full after couple mouthfuls of food, feel faint at times, fever.

Diverticulitis. See your doctor for a ct scan of abdomen to make sure you don't have diverticulitis and may need antibiotics and/or surgery. Try to avoid perforation of bowel.
Time for a checkup. If you have had these symptoms for more that two weeks, it is time for your to see your doctor.