Hi, I can understand what you are going through. It seems you have developed some inferiority complex about yourself. You emotional lability stems out from your inability to cope up which is causing problems. To call it depression, one will need more details about your daily routine, sleep and appetite. But there is no doubt that you need help, either in form of medications or psychotherapy. I would strongly advise you to meet a psychiatrist immediately. You also need to start talking to someone in the family whom you can trust and express your inner feelings. Start exercising on a daily basis and try to fix a daily schedule for yourself. Best wishes.