I spend a long time in the toilet this morning – so long that the prefect in charge of getting us all ready to go down to breakfast puts me on report for dawdling. I tried to flush all the soiled paper away at once and it blocked the loo, and then I drank a lot of water from the tap trying make myself feel less thirsty, and then I had to get dressed making sure none of the other boys saw me from the back, just in case, so that took longer than usual as well.

I take my usual place in Hall, but though I drink my fruit juice and some milk, I don't eat anything. I say I'm not feeling very well, and the prefect just grunts crossly as if he thinks I'm pretending, just to get sympathy.

The pain hasn't gone away. And actually, even apart from that I don't feel well at all. I don't want to eat, I don't even feel hungry, though I'm thirstier than ever. I feel cold all over and every now and then I feel dizzy.

And people are looking at me.

And whispering.

And there's a lot of laughing going on, especially among the nastier boys. Though some of the girls look a bit sorry for me, so it's not long before I stop looking around at all and just sit staring at my plate, which is blindingly bright white and seems to be getting closer and then further away and then closer again, which is very odd but not something I seem to be able to worry about as much as I suspect I ought to.

Sitting through Morning Assembly afterwards is agony; the children in the Lower School have to sit on the floor. By now it feels as if the whole bottom half of my body is melting, and I have to sit cross-legged, perfectly still and upright, and look as if I'm paying attention to what the Head Teacher says.

I don't hear a word he says, actually. I'm too busy holding in the screams that are crowding in the back of my throat, blinking away the tears that are perpetually gathering on the edge of my lashes but must not fall. Because the thing that I've been dreading wants to happen, and I don't know how I can stop it or bear it. I crossed my heart that I wasn't going to die, but I'm terrified that the pain this time is going to be so bad that I won't be able to bear it and maybe I will die, because no matter how slow and gentle I try to be I'm already hurting so much down there that I know it's going to make everything a hundred times worse.

But I have to go. I have no choice.

When Assembly ends I'm slow getting up. Some of this is deliberate, but mostly it's because I have to be so careful breathing. But I get what I wanted: when the form files out of Hall, I'm the last in the line.

The corridors are always a bit chaotic, with the various forms hurrying to their first classes, so I don't have any problems slipping away unseen. I walk as fast as I can without running, heading for a small pair of toilets tucked away down a side-passage. I've used them before, and there's hardly ever anyone in there.

Luck is with me. There's no-one inside, and with my tummy already somersaulting I rush into the cubicle.

For a few minutes, I think I really am going to die. I don't know how anyone could bear this much pain without it killing them. Fortunately the room's still empty and the door's closed so I can get a little relief from not having to keep completely quiet, though I daren't make a lot of noise even so in case someone passes outside and hears me.

When ... it's over ... I grab handfuls of toilet paper. It comes away feeling disgustingly wet and heavy. I don't look, just keep grabbing and wiping, hoping it will stop, but it doesn't.

I have to get to class. My form tutor Mr Fletcher doesn't like people being late for class, and I'm already in trouble for taking too long to get ready this morning.

I grab more paper and wad it up, just as I did when I got dressed this morning. I've put two pairs of underpants on so I wedge as much as I can inside them. I'll keep my blazer on so no-one will be able to see the bulge underneath them – we're allowed to, if we feel cold, so that's all right.

I pull my trousers up and fasten them. My fingers don't seem to be working very well and I'm cold and shaking. I don't look into the bowl before I flush the toilet; I don't dare, but I can smell blood.

Lots of blood.

After I've washed my hands and dried them I make the mistake of looking into the mirror. My skin's usually quite pale, but now it looks the colour of a peeled apple. My lips are blue, my eyes huge and stark with fear as I take in the awful sight of my reflection.

Get to class. I can get to class and sit down. If I can only do that I'll manage somehow.

Everyone has got into their appointed classrooms by now. The bright corridors are empty and echoing as I stagger down them. Nothing around me looks quite right any more, and there's a funny buzzing sound in my ears; and to make things worse, my legs aren't working very well, and it seems to take an astonishing length of time for me to weave drunkenly to the end of 'A' Block where our form room is.

But finally I get there. I can just about hold myself up while I fumble miserably with the door handle, making so much noise struggling with it that I half expect Mr. Fletcher to jerk it open and stand there glaring down at me.

He probably does hear, but when I finally manage to work the latch and heave the door open with what feels like the last of my strength he's like everyone else in the class – waiting for me to crawl in and make my excuses. I know from his face as I look across at it that he's shocked at me for being late, and arriving after all this time means he'll have to put me on report too; and tomorrow evening I'll be in the Head's office again and Mother and Father will be there too, and hearing what a dreadful little boy I am.

Reeds don't cry. Reeds don't cry. "I – I'm sorry, sir," I mutter, holding on to the door handle as the world starts swaying around me.

My mouth can't remember how to say the rest of it, though I see his face change and he stands up at his desk, very fast. Everything goes very blurred and the buzzing in my ears gets louder and louder, and then I can't hold on to the door handle any more and the floor comes up and hits me and a girl starts screaming and then another starts and there's so much screaming and shouting, but I can hardly hear it for the buzzing which is deafening me now, and the last thing I see is Mr Fletcher bending over me and roaring "Ring for an ambulance!"