My boyfriend said that his legs feel very heavy. He said this has been going on for a couple of days now. He is 54 years old. He has takes prescription medication for his high blood pressure, diabetes, and high cholesterol. His left leg (around the knee) was hurting him very much for about a week, so he went to his Doctor who sent him for an ex-ray. Nothing showed up on the ex-ray. So, his Doctor gave him some pain pills to take. It hurts him still. But, today he told me that both of his legs feel heavy. What could be causing this?