It could be diabetic neuropathy which is a problem with the nerves in the legs and feet. Many diabetics have this as it it a common complication. It can lead to pain, stinging, tingling, burning or a feeling that someone is stabbing you all the time. It is not very nice and can be very painful. Or it could be a problem with the circulation in his legs as high blood sugars sort of blocks the blood vessels. I am sure there are other possible but less common problems that could cause this too. He should not be afraid of mentioning the problem to his doctor as there are some very good medications that can relieve his pain. Sometimes reducing the blood sugars can help reduce the pain too.

Losing large amounts of weight is also a common symptom when people are first diagnosed. Is is caused because the kidneys cannot cope with the high blood sugars and chucks it out in pee. When diabetes was first recognised it was known as the melting disease. The weight loss should calm down as he gets his blood sugars under control.

However, 2 months is not long to get diabetes under control. It took me about 6 months. He needs to work hard and be very strict about his diet.

Oh and don't forget the exercise! It is very tempting not to make the effort to exercise when you hurt but exercise helps the insulin in his system to work so he should do what he can. Anything is better than nothing.