I have been a sleepwalker since I was little. A friend I once shared a bedroom with described how I got up in the night and went for a wander, talking to myself, before climbing back into bed. On another occasion, a hotel receptionist had to guide me back to my room after I appeared at his desk. Apparently I sleepwalk with my eyes open, but I know nothing of what happens until I am told about it the next morning.

These episodes have always been treated as a bit of a joke – when I did a night-time tour of my boyfriend Carl’s house one night before returning obliviously to bed, we laughed about it the next morning, barely acknowledging what a lucky escape I’d had. But it happened again.

Carl was living in an old terrace house with a very steep flight of stairs leading up from the front door to a landing outside his bedroom. At the bottom of the stairs was a cramped space with just a radiator and a bare laminate floor; across the landing from the bedroom was the bathroom. Perhaps I’d walked to the toilet in my sleep and, imagining I was in my own home, stumbled on the way out.

At first, Carl assumed the crash that woke him was a break-in, then he realised I wasn’t beside him. As he reached the top of the stairs, our friend Kate, who was also staying that night, emerged from her room. When Carl saw my motionless body at the foot of the stairs, his first instinct was to rush down to move me. My knees were drawn up into my chest, my face was bloody and more blood had pooled underneath me. But Kate, a nurse, warned Carl not to touch me, checked I was still breathing and called 999. I don’t know at what point I became conscious of what was going on but I remember the voice of a paramedic saying, “Well, that’s definitely broken, and I suspect that is, too.”

At the hospital, I drifted in and out of consciousness and had a full body scan to find out the extent of my injuries. Some were obvious – both my wrists were broken, the right one at an impossible angle. It appears I’d thrown out my arms as I fell and my hands had taken the full force of the fall, then I’d slammed face-first into the radiator in the hallway. That accounted for my broken eye socket, cheekbones, jaw and nose, as well as all the blood. I’d broken ribs as well, and sheared off part of a bone in my neck. But it was when a doctor told me my back was broken that I felt real fear.

“Will I walk again?” was the first thing I asked. I learned I was suffering from a compression fracture – one of the vertebrae had collapsed in my lower back, an injury that could be mended over time with the use of a back brace. I was given an epidural to control the pain and, over the next few days, underwent surgery to fix my wrists with metal plates, while other broken bones were set, stabilised and realigned.

My daughter, Olivia, who was six at the time, had been staying with my mother on the night of the accident. When I got home after 10 days in hospital, she started to call me “Metal Mummy” and took great pride in helping me put on my back brace each morning – I had to wear it for four and a half months. I struggled with the simplest tasks at first; my broken wrists meant I couldn’t even grip a cup. Carl had to lift me out of the bath.

Three and a half years on, I still experience back pain and my wrists can swell suddenly. As concussion can last for years, I feel sick and dizzy a lot of the time. There have been other somnambulistic incidents since: I was given a Fitbit last Christmas and it sometimes suggests I’ve been awake and wandering around during the night. My daughter has walked in her sleep a couple of times, too, but it’s not something I make a big deal of – we’re safe in our own house as we know the layout.

Even though I was very wary of stairs at first, I recognise that what happened to me was a freak accident. We still stay overnight in other people’s houses and we’ve not stopped going on holiday – I might as well say, “I’m not going to cross the road, just in case I get knocked over.”

• As told to Chris Broughton

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