As posts here confirm, these 'split second' thoughts are very common,m but few people voice them because of a fear of being thought odd or irrantional.
We holiday in Spain most years at the same hotel, and we always have a high floor - 9 or 10 - overlooking the Med. I enjoy the view, but i can only sit on the balcony for about five minutes before i feel the urge to jump. I know that I won't, but the feeling is strong enough to make me feel uncomfortable. i could no more sleep on a balcony than fly to the moon!