I Am a Teen With Depression

My friends used to always try to scare me, they would come up behind me and either scream or make other loud noises. I seemingly never reacted to them, but what they don't know is that everytime they did that my heart skipped beats, I stopped breathing, and I froze in place for a split second. Afterwards I played it off as nothing and eventually they got bored because I never reacted like the others and they stopped. Whenever they did that I would remember my first traumatic experience. The time I found my next door neighbor/babysitter after she committed suicide. I was about 6, all I really remember when I opened her door was an ear piercing scream, lots of blood, a lifless body, and a kitchen knife. I had to call 911 because her father was in hysterics, the only problem was that I was too late. It's been 10 years but I'm still affected by my experience.