Sometimes, taking an internet quiz on a random Tuesday night can change your life – first for the better, then for the worse.

Are you bothered by intense stimuli, like loud noises, strong smells or caffeine? Are you deeply moved by the arts or nature? Do you become overwhelmed when a lot is going on around you? Do you have difficulty with big changes?

For as long as I can remember, I’ve seemed to feel life more intensely than many other people. I move through my days flayed open, exposed to the world. I can smell food, the ocean, flowers when no one else seems to. A beautiful sunrise will send me into ecstatic rapture. I am fascinated by and in awe of the smallest daily occurrences. Large social events such as weddings can leave me overwhelmed to the point of dissociation. Once, when driving on the freeway, I saw a driver swerve to intentionally hit a brown snake with his tyres. I sobbed so hard I had to pull over. Because it wasn’t just that snake. For a moment, that cruelty and suffering seemed connected to all other cruelty and suffering, part of the same invisible weave, and it was all happening now. Could anyone else feel everything all at once, I wondered.

Then the quiz. A label. I was a Highly Sensitive Person.

The term “Highly Sensitive Person” (HSP) was coined by the psychologist Elaine Aron in the mid-1990s. According to Aron and subsequent researchers, HSPs have high levels of sensory processing sensitivity, a biologically influenced personality trait (like introversion and extraversion) that is built into the nervous system. The theory is that the HSP is more responsive to stimuli, processes experiences more deeply, is strongly attuned to aesthetic influences, and lives with a vivid, complex inner world. While not a disorder that may be diagnosed by a psychologist or through an official test, studies have found there are differences in brain regions of people high in sensory processing sensitivity.

After the online quiz, I read everything I could about my newfound label. I signed up for an email newsletter for HSPs and treated it like a bible. There were philosophical quotes, photos of bookshelves and lush forests, discussions about the ache of being human. These were my people. This was me. I felt seen.

It wasn’t long before being a HSP became suffused with my identity. I slipped it over my head like a jumper, wrapping both arms around my body tight. It was comforting, validating and empowering – until it wasn’t.

Seven Ordinary Sounds HSPS Should Avoid, the online article headlines read. Why Highly Sensitive People should identify their triggers before every social situation; Eleven Things HSPs Must Have to Feel at Peace.

I mostly considered being a HSP a gift. It charges daily life with beauty and meaning and infuses my writing with more depth. But I also recognised its downsides, and had sometimes struggled with the challenges of feeling everything so deeply. But now it seemed I need to protect myself, to curate my world, in ways I hadn’t even thought of.

The newsletter and social media accounts I’d started to follow told me there were things I could and couldn’t do. Things I must have to feel peace. They told me that I was fragile, always at risk of collapsing with burnout. They gave me a daily to do list, items such as “environmental scans” to avoid undesirable stimulus. There was a link to a hat with the word “overwhelmed” printed on the front. This online world taught me to turn my personality into a pathology, to view all of my experiences – past, present and future – through the lens of my label. When I did this, the world went from being an occasionally stressful place to one full of landmines – threatening, triggering.

I became very good at privately rehearsing future events in my mind in the name of self-preservation: if I go to those birthday drinks for too long then I will feel overwhelmed and I won’t have a good sleep, then I’ll be really tired tomorrow but my coffee will give me a headache, then I won’t be able to concentrate during this work phone call, and then and then and then. I listed my fears until they felt like facts, my thoughts pulling me along by a phantom leash.

I soon realised that I’d created a mental cage out of my sensitivity, transforming it into anxiety. The more I focused on it, the more stressed I felt, and the more I needed to control my surroundings to protect myself.

In recent years, self-labelling and self-diagnosis have become increasingly common, as people turn to online information, symptom language and identity frameworks to make sense of their inner experience. But experts warn this can sometimes be more harmful than helpful.

“These days, because we have access to so much information and certain psychological diagnoses and presentations have become part of the general discourse, self-diagnosis can be a problem,” says Hannah Jensen, a clinical psychologist on Victoria’s Surf Coast. “Some people may become hyper vigilant to symptoms of the self-diagnosis, which may lead to heightened distress without the support of a qualified professional. The diagnosis could also be incorrect, or people could be over pathologising appropriate emotional experiences – for example, sadness or grief could be labelled as depression.”

I’d gained a label that made me feel understood, but I’d lost the ability to see my life for what it is: moment to moment experiences I can react to as an individual human being, not a personality trait that dictates how I operate in the world.

I wanted to enjoy the “good” without suffering the “bad” of being a HSP, but I also didn’t want to live inside a bubble-wrapped universe of my own making. Was that possible? I began to wonder if I had more power than the label had taught me.

The brain, it turns out, is extremely malleable when it comes to how we respond to the world. Over time I’ve learned cognitive retraining techniques and grounding practices – but mostly I’ve learned that sensitivity is a biological tendency, not a fixed identity. My nervous system may be wired a little differently but my attention is still mine to direct, and when I stop scanning the world for threats I’m more available to notice the sheer magic of being alive.

I unsubscribed to that newsletter, and now my life involves very little overwhelm but just as much beauty and awe. Before, I felt seen. Now, I feel free. I know which one I prefer.

• Miranda Luby is a writer and journalist