I have had my aorta replaced in 1995, a femoral bypass in 2013, a mastectomy in 2013, been diagnosed with lymphoma in 2003. Recently, when I walk a hundred feet or so, my legs get weak and my stomach hurts. Is this a sign of another blockage in the arteries? When I am sitting down or lying down, nothing hurts, but walking or standing is not something I can do for very long.