Although I can't speak for anyone else but myself, I will answer your questions based on my own experiences and observations. I apologise for the wall of text and six-in-the-morning-mistakes.
Insomnia?
I can always tell if I will able to sleep or not, however I often find myself staying up all night, not because I don't want to end the day, but because I am in a state of mind where I feel like I need to finish my strain of thought and find some sort of conclusion.
Procrastination or laziness?
If I ever procrastinate or simply don't do something I am supposed to do, that is a decision I made the moment that task was given to me. Note that I wrote given. If I don't see the purpose of or don't agree on something, I won't have the proper motivation. If I don't have the proper motivation, I'll do my own thing instead. However, if I am properly motivated I will work way harder then most people, once I set my mind to it I am dedicated as hell.
narcissism? IQ?
It is my life, so yes I am way more invested in it than anything else, however I don't value myself higher that the next guy. I do spend a lot of time thinking about how I appear both in looks and conversation. I don't take IQ scores too seriously, however I scored 128 on the official MENSA test and I know that it would really bother me if I had a lower score because intelligence is something I value highly.
INTJs are often regarded as "cold"; do you feel that's true or not?
Personally I care a lot, I am interested. I don't have a desire to express it, though. A lot of people whom I interact with think I am a gray, melancholy dude who don't care or see the beauty in this world. I might appear like I am better that them, this is not intentional, I just like to focus on the things I find important rather that making sure they know how I feel about stuff.
Do you feel that you easily pass as smarter or more knowledgeable than you are?
I believe people have a hard time deciding, because I give them little to work with. Therefore I pass as more of a misery than anything else. Once I let people in to my life on a deeper level, I have been told that they appreciate the way I view things, and that I often have something interesting to add wich they never would have thought of on their own. I really appreciate that, because it is something that is important to me, for my own sake.
Do you find that you're great in an emergency?
Surprisingly, yes. I am horrible when it comes to conflicts, if there is an issue I often tend to do nothing and stay inside my mind. However, once there is an emergency I'm often the first to act, and I'm not afraid to act drastically if I think it is for the better good.
How do you think you would react if someone suddenly pulled a gun on you or trys to start a fight?
Well, if someone let their emotions get out of hand, I'll get away from that situation as fast as possible. If it can't be solved by a discussion, then I'm not staying.
Do you think you could murder someone?
This is something I have been struggling with for a long time. I know that I could, without a problem, do it. Everyone have the right to life itself, I view it as one of the most basic right of all, something no one can take away from you. If someone, or myself, wanted to, or I knew for a fact that it would have an positive impact on a lot of people, then I would be able for sure.
Opinion on being the "Alpha male"?
Do whatever you feel like, I don't really care. I feel like being more natural while I prefer a somewhat feminine girl. If someone wants to be a certain way, go for it, there is no right or wrong.
TL;DR: How I am as a person, I am confident in my own conclutions and act acordingly, and like to listen to what others have to say instead of telling them stuff I already know.