hey AvereX, that happened to me too. When I was younger my sister used to annoy me so much (sibling rivalry) but she made it more problematic by being an ENFP and kept trying to get me to like her, but it only exacerbated the whole thing. So I'd sit in my room after particularly annoying episodes involving her, and start imagining torture scenes in which I'd rip off her head or strangle her or tear her apart from limb to limb.
Then I'd start questioning myself about how psychopathic I am.
I grew out of that of course, and it didn't happen to anybody else other than my sister. But now we're great friends and all. And no, I don't think it's normal
AT ALL.