OK, so this sounds big-headed, but I’m generally quite good at things. I’m lucky that I’ve had a generally straightforward kind of a life; crossing the usual developmental hurdles without much hassle.

I was, apparently, slow to potty-train, but after that, things progressed pretty smoothly. My exams all went the way I needed. As a teacher, I moved gracefully up the pay spine until I became a head of department, and it seemed to go OK.

A year after getting my promotion, I still liked going to head of department meetings. I was proud when people listened to what I had to say; I liked making decisions; I liked forward planning; I even liked filling in my department development plan. I suppose you could say I was a big fat swot. I didn’t mind being square - it was a part of my identity.

So the whole parenthood thing came as a bit of a shock. For once I didn’t have all the answers, and books were only going to get me so far. I’ll never forget the night we brought our baby home; at 3am, my husband and I were desperately thumbing through the index of our baby manual, looking up “c” for crying to see if we could figure out why our baby wouldn’t shut up.

Was he hungry? No. Tired? Dirty? Ill?

After we’d answered no to all the key questions, we looked at each other, sleep-deprived and stumped. The book had run out of answers. Was there a reality independent of the book?

Strangely enough, our baby seemed to prove there was. Throughout his first few months he has proved himself resolutely devoted to existing outside of the manual, determined to force his goody-goody parents to think for themselves.

It’s been a big ego check to go from being at least a small slice of the big cheese at work, to being just another tired mum pushing a buggy round the park. In the world of motherhood it doesn’t matter how many points you’ve got on your pay scale, we’re all helpless in the face of our adored offspring throwing wobblers in the most inappropriate places.

My baby has developed a habit of waiting until a room is hushed and quiet, before doing an enormous burp while beaming with pride in his new abilities. It’s definitely a way of getting attention, though I’ve told him I don’t want him doing it when he’s 18. Motherhood is teaching me for the first time to depart from the rules and get over myself. It’s truly humbling. I’ve had to get used to not being good at anything. I’ve had to learn that my baby is an independent person, and sometimes - well, often - I can’t affect his behaviour. Far from sailing a smooth course through life’s trials and tribulations, I’m having to negotiate a far more stormy passage.

I haven’t completely given up on being a boring overachiever. I’ve started an MA in literacy difficulties, but it’s not exactly following in the path of my earlier successful studies. Staggering in late every Thursday evening for my class, realising I’ve brought my baby changing bag rather than my school bag, I’ve winged it through lessons clutching a pile of wet wipes and baby lotion rather than the required reading and my notebook. My baby puked on my homework, honest miss.

Paralysed with guilt at leaving him, and wrung out with the emotion of missing him, I’ve talked about him incessantly when we’re supposed to be reviewing case studies, and I keep my eyes on my mobile, rather than the PowerPoint presentation.

Last week, for the first time in my life, I gave in an essay I’d hastily written the night before, without even proofreading it by reading it aloud three times in front of the mirror. My Year 10 English class would be proud. Looking at my sleeping baby when I finally get back at night, I wonder how something so small could be causing, quite unintentionally, such an inner revolution.

Gemma Warren is on maternity leave from her job as a Senco at a north London comprehensive. Email: gemmablaker@hotmail.com