I had a day off today so, rather than languish in after-school club, my eldest came straight home. As an added bonus, he brought a classmate with him. It was a pre-arranged playdate. I was the one who organised it but believe me, I really wished I hadn’t.

I cannot stand playdates. Each one constitutes several hours during which I constantly feel seconds away from total heartbreak. The tension is unbearable. I’m the only one who feels it, but I’m not the one whose heart would be broken. It’s my son for whom I fear. I can’t stand the thought of him being hurt.

It’s ridiculous. He’s forming relationships with other children and of course he will get hurt. There will be arguments, and fights, and upsets. That’s all part of being human, and it’s how he will learn about the world. I still can’t bear to think about it. Any hurt will pass, but in the meantime he will suffer. I don’t want him to.

I worry about the hurt being his fault. I know that when I was a child, it often was. I was selfish and mean. I had a short temper. I had, and still have, the capacity to act like a total twat. What if he’s inherited all that? Or if not inherited it, surely he might learn it from me?

I spend the whole playdate in the kitchen, wringing my hands. They don’t like me to be in the living room. They want to do their own thing, which mostly involves playing on the Playstation. I bring them orange juice. They don’t look at me, but then they barely look at each other.

Sometimes my son snaps at his friend for not “playing properly”. His friend is an only child. My son has a younger brother, whom he’s used to bossing around. Sometimes he gets muddled and calls his friend by his younger brother’s name. I’m thinking please be nice, please be nice. Please don’t mess things up. I want everyone to see how amazing you are, and to love you.

Eventually they stop for tea. I have cooked fish fingers, new potatoes and peas. Proper mummy food, like Sally on Coronation Street would make. My son’s friend says the peas are too small, and that he doesn’t like the skin on the potatoes. I tell him I’ll remember for next time. Inwardly, I am pleased, as this exchange indicates my son’s friend isn’t perfect. If both boys can be total sods, then surely they’re in with a chance.

The friend’s mother calls to pick up her son. The boys are still playing together. Nothing has gone wrong. I am relieved. My son hasn’t messed up, not yet. Just as they’re about to leave, my son’s friend turns round. There’s one last thing he wants to do.

During their playtime he’s been absent mindedly filling an Early Learning Centre washing machine with Lego Star Wars Storm Troopers, a mass of jumbled white plastic. Just as they’re about to go, he decides to toss Lego Darth Vader into the mix. Seizing on an opportunity, I decide to make an appropriately mumsy quip, just to seal the bond between mothers as well as between sons:

Ooh, careful there! You don’t want to mix your colours and your whites!

Which would, I think, have been an okay thing to say. Only it crosses my mind that we are talking, not about random Lego pieces, but about little men. And suddenly I’m terrified I’ve said something potentially racist. At which point the best course of action would have been to carry on with the conversation and hope no one else had had the same thought. But I am not like that. I am, on the contrary, a total twat:

Sorry, that might have sounded a bit racist, really. I didn’t mean it like that! I was just meaning, like, you shouldn’t mix things in the washing machine so the colours don’t run. But I don’t think that about people. Not even Lego people in a pretend washing machine! No, I’m not making a judgement on that. I’m bringing them up to understand that all relationships are -

At which point my son’s friend and his mother start backing away, smiling politely, but there’s fear in their eyes. My son seems oblivious, thankfully. I am filled with shame and horror. Why am I such a total idiot?

We have another playdate arranged for next week. This time at my son’s friend’s. I will worry. Four-year olds can be really foolish. But it’s the 37-year olds you have to really watch out for.