You really should see a doctor, as symptoms of depression can actually be caused by something else. It could be food allergies, vision or hearing problems, vitamin or hormone deficiencies, etc. I had problems with it for a long time, and finally found a good Dr that did extensive tests to root out the problem. The first thing she found was Hashimoto's disease, which is a disease of the thyroid, and a lack of thyroid hormone can wreak havoc in your body. That only takes one little pill a day to fix. The next thing she found was MS, which is more serious, but still it was nice to know there was a tangible reason for how I had been feeling for so many years. Get to a Dr and talk to them and make sure you tell them you want bloodwork done to check for any physiologic reasons why you may have symptoms of depression!
Take care of yourself, and go hug a chicken!