Agree with going to see your doctor, to be honest I think part of your hesitation to go see the doctor may be inducing further stress/anxiety. Just remember that you are not alone, a lot of people are/have been in similar situation as yourself. It's okay, take a deep breath you can do this.
This is not directed at you but I must address this - there's nothing wrong with depression/being depressed (other than depression itself).
It's more common than people know or would like to openly talk about. It's a shame that it's so heavily stigmatized because it can happen to perfectly normal
sane people at any time in their life, unexpectedly. By all means being depressed does not mean one is crazy. What does crazy mean anyways? I'll digress on that. Don't forget depression varies widely in severity, length of time, symptoms, etc. Same goes for treatment, it can be as simple as getting some exercise (endorphins), writing in a journal, talking to a friend, seeing a therapist, taking medication all the way to radical type treatments. I'm not an expert by all means but you get the jest.