I am contemplating trying on another pair of very skinny jeans that are languishing at my feet on top of a pile of other similar very skinny jeans that I have just tried to struggle into.
I should put my pants back on, I'm thinking. It's not nice for the next customer if I do not. I don't think I'd like to pull on a pair of jeans that someone tried on before me without their pants on but if I try the jeans with my pants on then they will most likely look like the last pair did: God awful, way too tight with digging-in knicker elastic showing through around the arse. Not good.
The lights are too harsh in here. I can kid myself that everything is more or less how it used to be in dim lighting. I can stand back a bit from the mirror at home, with the curtains drawn, and see, or think I see, a semblance of what I used to be, but here it's unforgiving.
The way the spotlight is raining down on me from above makes me feel like a specimen on a petri dish. It's highlighting the deep recesses beneath my eyes, the lines that have recently formed crevasses down each side of my mouth and every sag and wrinkle spoiling my once-I-was-proud-of-it body.
Add to this the heart-thumpingly loud music, the fact that it's incredibly hot and that I just had to wade through swathes of nubile young flesh to get in here and it's dawning on me that this isn't the go-on-just-treat-yourself-for-once outing I had envisaged.
I've just waved Youngest off on the train at King's Cross for a half-term break up north with his grandparents and cousins (so at least someone is having a holiday), leaving me with the relative freedom of only two older boys back at home who are this very minute dropping a trail of wet towels and dirty clothes behind them like gingerbread crumbs, before redecorating the kitchen with pancake mix. But at least I don't know this yet.
I also don't know that this will be the only time I am alone, at all, even for a moment, for the next nine days so I should be enjoying myself. I should not be sweating to death in a changing cubicle in Topshop.
Who am I kidding? What on earth am I doing here? I'm old enough to be a grandmother to most of the girls I just slid past on the way into this hellhole. Okay, I can still get into some of this stuff, particularly the cute little 50's-style dresses I am so fond of, just about, but does that make it right? No.
The bottom line is, as it were, I don't want to be that person I hardly recognise staring back at me in the mirror. I want to be young again. Or at least younger. I want to be the person in the book I just read and couldn't put down: 26 year-old Cheryl Strayed: blonde, beautiful, American, who walked a thousand miles along the Pacific Crest Trail from somewhere in California that I can't remember, to Portland in Oregon, by herself, having mind-blowing sex with a stranger along the way and 'finding herself' in the process (not during the sex, you understand, although I'm sure that helped). You might have heard it on Radio 4, it's called Wild.
I couldn't put that book down and I think it was because, quite apart from the stark contrast between the landscape she evokes, all rolling hills and expansive vistas, and the cold grey south London streets in February that are all around me just at the moment, it was the sense of freedom she describes, of a life pared back to the bone, that appealed so much. And she was young and unencumbered, while I, standing in Topshop, looking in the mirror, have to accept that I am neither.
I am a middle-aged mother of three, half-naked in a changing room on Oxford Street, trying to get into a pair of skinny jeans that are much too small/young for me.
P.S. As a compromise I tried them on with just my tights underneath in the end and they didn't look too bad so I bought them.
But now I think I'll take them back.
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