If my kidneys are barely working, can my kidney function ever return to normal?

Rarely. The answer depends on whether the kidney dysfunction developed quickly or over a long period of time. If there was something that caused the kidneys to fail that can be corrected such as dehydration or a medication, the kidneys can recover. However if the condition developed over many years associated with a chronic disease such as diabetes high blood pressure or glomerulonephritis than the likelihood of recovery is low.