When I told people that I was publishing a book, some of them were very surprised, but a fairly large number of my mates were just like, "oh, of course. Why wouldn't you write a novel and get it published?" Because, obviously, once you've written the thing, publication is the next logical step. Clearly.

Strangely, the people who were most surprised were the people I work with. Which might seem weird because I work in a publisher where, by definition, books get published all the time. So you would have thought that they would be the one group who would see publication as normal and everyday.

Except actually that's not how it works. I suppose it's a bit like being a costume maker at the ballet – if you're back-stage you see the sweat and the failures and the unglamorous side of it all. You see the dancers coming off with blood in their pointe shoes, and watch them get sprains and broken bones. So, rather than seeming more ordinary, the quiet perfection of the arabesque only seems more miraculous.

No-one was more surprised than me. I had been writing books - stories really - for years, but they all went under the bed. The first ones, written while I was at school, were just plain not very good. Then, later on, I'd started to work at Random House in the publicity department. I loved the job, but the side-effect was a huge attack of stage-fright about my own writing.

It's easy, when you go into a bookshop as a punter, to see the thousands upon thousands of books lining the shelves and think, surely, surely there's got to be a place in there for me?

What you don't see is the underside of this iceberg tip. The hundreds upon thousands of manuscripts that never made it. The ones never finished. The ones rejected by a slushpile reader. The ones rejected by the agent's assistant. The ones rejected by the agent. The ones rejected by the editor and - most heartbreaking, perhaps, for a writer - the ones who make it all the way to the acquisition meeting only to fall at the final hurdle.

And when you work all day in a department surrounded by the very, very best writers - Booker winners, Orange Prize winners, Nobel Prize winners for crying out loud! - well it's hard to take a page of your own writing and appraise it in a realistic light. Is it as good as JM Coetzee, Rose Tremain, Julian Barnes? Clearly not, no. Ok, back in the drawer.

But perhaps one thing all writers share is John Donne's "itch of writing". The feeling of having words inside you that must get out, an itch that needs to be scratched down on paper (or tapped onto a screen). The words kept coming. And at last I wrote a YA book.

In one way this was the most unhelpful thing I could have done. It was a genre I knew little about, represented by agents I'd never met, and published by editors I didn't know. I had no contacts, no insider knowledge. But in another way, it just what I needed. Suddenly I was an outsider again. I was the punter in the bookshop, looking at the YA section and thinking "well, it's huge! Surely there must be a place for me?"

So I subbed - like any other punter. To the agency slushpiles. And I got rejected. Which was exactly what I'd expected so no surprises there. But I tweaked, and edited, and resubmitted - and this time I didn't get rejected.

I'm still getting over the surprise.

A Witch in Winter by Ruth Warburton is published by Hodder Childrens.