My partner’s head was between my legs when I felt a splitting pain at the base of my skull. It was as if someone was trying to crack it open with a teaspoon – as if it was a boiled egg about to spill its yolk. At 24 years old, I had chalked up my fair share of experience, but this was a new sensation at the height of orgasm. Even so, it was 3am and neither the worry nor the pain stopped me from falling asleep.

The next morning, the pain was still there. It had dulled to an unpleasant throb. At the time, in 2017, I was between jobs, so I put it down to a stress-induced headache, but I booked an appointment with my GP just in case. I told the doctor about the previous night’s events and showed her where the pain was. Apparently, it is not uncommon for pressure to build up in the blood vessels leading to the brain during sex – but, on rare occasions, this can cause a berry aneurysm to burst, leading to a dangerous bleed. She told me this in a tone of alarm I had rarely heard from a doctor, then faxed the Royal Free hospital in London to let them know I would be coming in immediately.

I felt surprisingly calm, and made the obligatory calls to my parents and my partner to let them know what was happening. This turned out to be a huge mistake.

I set up camp in a corner of A&E and – grateful that I had a book with me – whipped out Hunter S Thompson’s Fear And Loathing In Las Vegas. I remember getting to the line “In a closed society where everybody’s guilty, the only crime is getting caught” because of what happened next. To my horror, my father rushed in, eyes red and watery. I had been there less than two hours, which meant he must have cancelled an afternoon of teaching his driving students in Bedfordshire and floored it along the motorway without warning me.

I should have focused on reassuring him, but my mind was racing – how to get my story straight? I ended up telling him the doctors thought there had been a build-up of pressure in my head caused by strenuous exercise. For most of the next 15 hours, I succeeded in keeping him in the dark. I rebuffed every attempt he made to accompany me to blood tests, for fear a medic would casually drop in the sex part of the story.

Eventually, I was called for an MRI scan and wheeled to a room where my father was waiting. Hours passed. There was talk of a lumbar puncture and a weekend stay. It was only then, when the prospect of a needle in my spine entered my mind, that fear overtook embarrassment.

Finally, a senior doctor appeared, flanked by two juniors. He started to speak. I blurted out: “Stop!” “Sorry,” I went on, “it’s just there might be some things in that report my dad doesn’t know.” I turned to my father and apologetically asked him to leave the room. As he walked out, I saw a familiar expression on his face – that quiet, what-have-you-done-now? parental rage. The doctors looked uncomfortable, but continued as if nothing had happened. “We’re pretty sure you don’t have a bleed to the brain now,” the senior doctor said. “It seems it’s just a sex headache.” I didn’t say anything. It sounded like a joke and I was waiting for the punchline.

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“As sexual excitement increases, pressure can build up, causing a dull pain in the back of your head,” the doctor explained. He told me I wouldn’t necessarily get sex headaches every time I orgasmed, but warned that the problem could last a while. “If so, you need to take painkillers beforehand.” The doctors left and my father walked in. “Are you pregnant?” he demanded. I reminded him that I came out years ago.

There is no easy way to tell your father that he has spent 17 hours in a hospital because you had been having earth-shattering sex. We left quietly and he offered to take me back to my parents’ house, but I couldn’t face the humiliation of telling my mother the story, too. I assume he relayed the details, but she has never mentioned it.

After my father went home, I called my partner to let her know I was OK. She was positively gleeful at the diagnosis. “Hold on, our sex almost blew your mind?” The headaches lasted a few months. And while, 18 months later, we are still having mindblowing sex, I haven’t had to return to the emergency room.

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