I don't even know if I have a special interest

I love so many things related to science fiction as a genre, and nearly all my favourite pieces of media are related to it in some way, but I feel like my interest isn't strong enough to count.

It's not what my entire life revolves around and the interest shifts focus. One month I might think about Transformers followed by interspersed weeks of thinking about Alien or a sci-fi story I read. For the past few weeks I've spent much of my waking thoughts and time thinking about or playing Doom. My music taste is varied but i adore synths in almost anything.

There's an overall theme here, but maybe I'm just generalising and it's too broad of a topic to be a special interest.

I do also like weird and surreal things in general. I am fond of horror as a tool and strange philosophical conundrums.

Sci-fi media has helped me understand myself and my surroundings better, and I do love it immensely. I don't really have anyone to talk to about it but I focus on it a lot nonetheless.

I just don't want to contribute to the trend of terms used by autistic people being watered down.

How do you guys define a special interest? If you have one, when and how did you find out?