Am i depressed?

Im 16, and have been feeling this way since i was 13. I’ve been feeling very numb, and ive always tought this feeling would just dissapear. I cant remember the last time i was truly happy, anytime i experience something nice, i emmediately start feeling sad because i know this moment will go away and i will go back to feeling numb. Also it feels like the world has desaturated if that makes sense.