haha nice did you try to play it with lower sound level and faster? for me, i can play the same game without any "fear" or shitting in my pants. if i play it with headphones and walk very slow i shit my pants, if i run threw the levels and sound only over tv, i feel nothing.
same with amnsia, like osed already said. if you really concentrate at the game in a dark room you shit your pants, if you play it in daylight and talk with someone at the same time, you feel nothing scary.