Generally, people who are depressed lose interest in the things they once enjoyed. Many start to isolate themselves and don't feel like carrying on a conversation. Some of your symptoms, like poor attention sapn can go along with depression, but there are enough symptoms that don't fit the profile that I'd say there is some doubt.

Realize that no one can tell you for sure, obviously we are not Dr.s here, but it would probably be a good idea to see a nuerologist. That doesn't mean you have a serious disease, but its worth having it checked out by someone who deals with the types of symptoms you are experiencing.

Have you taken any of the quizes for depression? They aren't a substitute for a Dr., but may give you an idea of how closely you fit the profile of someone with depression.

Anti-depressants can cause orthostatic hypotension and lack of appetite, but again, I really think you need to see a neurologist. I wish you luck.

Sam2