I am having a lot of pain in my legs. Could it be diabetic neuropathy?

The typical leg pain associated with diabetic neuropathy usually presents as burning or 'pins and needles' or even numbness in 'stocking ' distribution involving both legs. It invariably is more intense overnight and may disturb sleep.  Sharp pains radiating down the leg from the thigh or lower back would suggest nerve root irritation and would more likely be attributable to problems in the spine. 

Does Metformin ensure that I won't have diabetes because of my PCOD?

Metformin is frequently prescribed for patients with polycystic ovary syndrome because it improves insulin sensitivity and restores menstrual regularity. It has also been shown to benefit fertility and may protect the pregnancy once the woman has conceived. Women with polycystic ovary syndrome are characterized by significant insulin resistance which may lead them to develop diabetes mellitus later in life. Metformin use does not guarantee that they will never develop diabetes. The Diabetes Prevention Trial has shown that metformin is no better than lifestyle change (diet, exercise) in preventing diabetes. Controlling our weight with a healthy diet and remaining physically active is the best protection against chronic metabolic illness, including diabetes.