I can't tell anyone I'm depressed

I'm 16 and severely depressed. I've taken every depression test out there, even ones on the second and third page of Google, and they all come back with 20+ points over severely depressed. It's been like this honestly since I could remember but I've started to notice how not normal these feelings are. I cannot tell anyone except strangers. I can't tell my parents, I have barely any actual friends, I can't tell doctors or counselors. And the worst part is probably that I'm one of those smiling depression cases where from an outside perspective, you'd think I was high off my mind because I look so happy. But inside is just a crippling empty soul needing help. I constantly turn to websites asking for advice but everyone tells me that I REALLY NEED to tell someone. I don't know what kind of answer I expect to get, I really wish I could talk but for some reason I can't even think about telling someone or my heart starts racing and I want to cry. I don't know what the right response to this question is, but maybe someone will say something I haven't been told yet. Thanks

Hello wholian!
First of all I'm so sorry about your feelings.
You say your problems is a depression, but mahibe you don't know that there are many kind of depression.
By the way, the major depression includes the following symptoms:
Feeling empty or feeling anythig,
feeling constantly sad,
having pessimism, hopelessness,
being out of interest or pleasures
becoming asocial, having guilt thoughts
Sadness and pessimism are so strong to lead you to suicide attempts.
Among the alterations of the autonomic nervous' functions is the symptom of insomnia, a loss of appetite and loss of sexual desire.

Tell me if you recognize some of your symptoms in this list.
However, don't be scared. You can overcome your depression and recover your psychological balance.

Have you ever tried to give vent? Try it now! Try to tell me what's going on. You're 16, a so young boy. What happens to this guy?

: )