For The Past Several Years I Have Had Difficulty Walking

For the past several years I have had difficulty walking and cannot stand for long periods of time. About a month ago I developed a cough and lost my voice for about 3 weeks... Now I am nauseous and cannot keep anything down for long ... And I also constantly going to the bathroom.. What is wrong? I have no energy and sleep all the time ... I went to the doctor for my cough.. I feel like I may pass out ..help?