Is The Exorcist Really That Scary?

It scared me as a child! Her head twisting all the way around. When she has the crucifix "stabbing" herself with it. I think there's one part where she's flicking out her tongue.. It was disturbing. Then I saw a part yrs later from the director's cut or something of her walking on her hands down a staircase and I think blood is dripping from her mouth.. I thought I was watching it alone but when I turned around my young niece was watching it too, her little mouth was frozen open.. Aww. I changed it of course.