If you're under 18, doctors tend to try and avoid prescribing anti-depressants although of course some people are given them (especially if you're near enough to 18). Don't be scared to go to the doctors: they'll most likely a bit about your history and how you are now, e.g. sleep pattern, appetite, mood, as well as why you think you're feeling the way you are and your thought processes. Chances are they'll try and determine how depressed you be: mild, moderate, etc, or if it's tied in with anxiety... Anti-depressants aren't for everyone. There are many different types, and some have side effects that affect people yet have no effect on others. Counselling or therapy can often be offered as an alternative, or in conjunction with prescribed medicine.
The best way to find out is to go, though: as obvious as it sounds, you won't be judged for going, and in the long term it'll definitely help, if only for peace of mind. All the best!