yes going to your doctor is a good idea, but you might also visit with a school counselor, or a pastor at a church (even if you dont go to church there, even if you do not go to church at all) , many pastors are trained counselors and if you have very little money (make sure you tell them) they will charge very little, often nothing. many youth pastors are also trained counselors and sometimes have more time to visit. sometimes we just need someone to listen. also take walks everyday, I've heard Yoga is very good for depression, you would benefit more by joinig a class.check the hospitals, colleges, clinic, newspaper, etc. get at least 8 hours of sleep a day, drink plenty of water, stay away from nicotine and caffeine as much as you can. find a hobby you enjoy.
Depression is a chemical imbalance in the brain. You need to see a licensed healthcare professional in psychiatry. After a complete examination and diagnosis,medication will most likely be prescribed. Should you not need medication to assist you with your depression, you can see a psychologist of licensed social worker to talk to and get to the root of what is causing your depression.