Disturbing Grotesque Dream

I'm a Dreamer, since I was a child I've had very intense dreams and nightmares. I'm now at a point where I can realize I'm dreaming within the dream. I'm so glad I was able to do this because this dream was fucked up. I was walking with some people in New York and I saw the Freedom Tower formerly where the Twin Towers were. Well, we were talking about what had happened as we walked past and suddenly everything got dark and destroyed. We were still walking and there was “debris” everywhere and we could feel it under our feet - squishy. Until we realized it was not debris it was piles and miles of dead body parts, everywhere. It was horrific and at that moment I started saying this is a dream, this is a dream, this is a dream. I can leave, change this, this is a dream and everything starts dissipating and I go into another dream. I don't remember if I was able to choose the next dream but I was definitely able to get out of that terrifying dream. Is this normal?