EggplantNot trolling but you might, just might, have a mild case of Tourette's syndrome. You probably don't, but those sort of persistent thoughts can be a symptom.
Not necessarily.Everyone can have these kind of thoughts.
Up to a certain level its normal dude, nothing to worry about. From being in traffic and thinking "I could probably kill 3-4 people right now just by going into the incoming traffic" to having devious sexual thoughts and stuff like that. Things that people would consider sick and disgusting.
99% of the time is just a passing thought, altough really uncomfortable. It's a sudden impulse thought that shouldn't affect anyone much, if it really starts affecting you and messing with your head then I might advise seeking help