Trying to describe a cycle I’ve experienced for years- wondering if anyone relates

I’ve been noticing a pattern in myself that’s been going on for years, and I’m trying to understand it better. I’m autistic, which I know can involve hyperfixations, but this feels very different from “cute” or casual interests.

Basically, I go through periods (usually lasts 2 weeks) where I get an intense need to hyperfixate on something- a topic, project, or aesthetic. The content doesn’t matter; I don’t choose it because I like it. I need to focus intensely on something, or I’d fall into a really hard depression. During these periods, my thoughts race, my energy spikes, I stim physically and vocally, and my sleep changes. I even talk to myself endlessly just to get some physical outlet.

The cycles don’t really end. What changes every couple weeks is the topic I latch onto- but the intensity, energy, and emotional weight remain the same. If I don’t find a new fixation quickly enough, I crash hard, mentally and emotionally. I’ve only recently started noticing this pattern because it takes so much energy to live through it, and it’s been my whole life. Even as a kid, I couldn’t sleep, I’d stay up all night, paralyzed by paranoia, just lying there until sunrise. That was my baseline.

It’s not euphoric or pleasurable in itself. It’s not like mania; I have awareness and some control over how I channel it, and I rationalize my actions. But it’s exhausting, mentally consuming, and has been shaping my life for years. I’m not self-diagnosing or claiming any label at all- I just want to understand my experiences better and hear if anyone else has cycles like this, or experiences something similar.