Is there any color change to the leg?
Is there any swelling or changes to temperature of leg?
Is there any numbness or tingling?
How long has this been a problem?
You need to see a doctor to be evaluated for peripheral artery disease. This is a common complication in diabetic patients and also occurs in overweight people too. There could be a problem with the circulation around the leg.
They will want to compare the blood pressure in the ankle with your normal arm blood pressure. They will also want to look at your long term glucose control.
With a sedentary job then you need to ensure that are getting exercise for at least 30 minutes daily, so using the time on the way to or from work , or at lunch to get some walking in will help maintain circulation. But you must see a doctor before you start to lose circulation to your foot.