@Laiste I am only assuming narcissism in my case just by the behavior but it's hard to say for definite as can't diagnose it.
In your case from what I have seen, I don't think you are a psychopath, personally. I can relate to you in some ways. I don't care about things most people care about, celebrities, people I don't know I don't really care about their lives when being told about them, it's like...okay but I don't know them. Chit chat I can't do, I can but I find it a struggle and boring to be honest. More if I have something worthwhile saying, I'll say it.
However, I have empathy and I think I have too much in a way because I feel others sadness or pain, it's overwhelming at times but it's for people I can relate to or know. Same with animals, I have a very strong bond with animals and can generally train and tame them, even wild ones seem drawn to me.
I have been suggested that I am autistic because my children are diagnosed and it aligns with how they are too. See things in a different light, more factual or logical in general without the fluff. I have been this way since young, wise beyond my years or in the wrong time I've had it said. However I often get used because I'm too trusting because I generally see the good in people.
Narcissism on the other hand which I think I've experienced is deceiving and cunning. My entire relationship has been a lie, I've been living with an imposter. The person that I met and married is not the person they are today.
Total lack of empathy, remorse or guilt. Everything is a manipulation in order for their own gain or to bring others down. See themselves superior than everyone else but deep down they are fragile and they can't accept that to the point of delusion. They must never be to blame at fault or in the wrong because if they are, they are not perfect.
If you criticize, blame or slight in anyway they will do anything to avoid it and if you like too deep something raw comes out. The real version of themselves reads it's head. I wouldn't believe it unless I saw it but what I saw was someone evil.
They act like different people depending on who they are with. They can be loud and extrovert with extroverts and introverted with introverts. They are all about public image and will be overly nice to maintain that view but horrible at home.
Positive and negative emotions they enjoy. They do nice things for people but not out of care but for praise and they hurt and make people sad because it gives them a thrill, while demoting that person and raising themselves.
It's like an angry demon child inside an adults body, much like that horrible boy from Toy Story. But it's wrapped in layers upon layers of different masks of someone else and they create new masks as they go.
That's what I've experienced anyway... there's more but that's the gist.