My hair is really long right now. So long I can chew it. And it’s big — Texan-televangelist big. Tons of wax and a westerly wind keep it vaguely under control. I don’t even like it. But I am resisting pressure to get it cut. Why? I am 27 and a half years old. If I get savaged by scissors now my hair will take two years to grow back. By then I’ll be nearly 30. Which means I’ll look like some twat trying to get down with the kids. This is my last chance to have long locks. So the mane stays, however inappropriate. It’s a trophy from my twenties.

We’ve no problem abandoning acne and all the ugly baggage of our teens. Au revoir to all that. Physically, socially and sexually, our twenties are supposed to be our peak. We twentysomethings are supposed to be hopping from gym to party to bed (with pauses in the boardroom). But it’s not like that.

It’s like this. You’re 25, but feel 45. You should be having the time of your life. But all you do is stress about your future-free job, scary debts, alleged friends and non-existent partner. If your life was a movie it would go straight to video. And nobody would rent it.

You’re not alone. Ask any twentysomething how they’re doing and they will bravely say, “fine”. They might well be. But scratch the surface and you’ll see that for many of us all is not fine. Not really. Far from roaring, your twenties are an extended mourning period. Wave goodbye to the metabolism which lets you eat anything and stay thin. Cry for the constitution which gets you over hangovers in hours not days. Watch in horror as your eyebrows turn to topiary. We stop growing and start ageing. And the freedom-responsibility balance tips as we are faced with the three Ms — mortgage, monogamy and marriage.

Feeling you should be having, doing or being more is the core of the “quarterlife crisis”. Suddenly, 30 is so close you can smell it and everyone is doing better than you (or seems to be). The excitement of graduation fades. Real life sets in. And it’s expensive, ugly and competitive. We feel stressed, inadequate and somehow not quite as good as our peers. We feel poorer, less successful and less together. We feel, even though we’re only twentysomething, that our lives are in crisis.

Why? Property has never been more expensive, work has never been so insecure and debt has never been so pervasive Yet we’re all supposed to be as carefree as the women in tampon adverts. “You worry too much,” says my mother, unaware of my five credit cards or the high-low realities of freelancing.

If, as we’re constantly told, the world is our oyster, it’s definitely a dodgy one. Unlike the midlife crisis, the quarterlife crisis is not widely recognised. There are are no “experts” to help us. We have no support apart from each other.

This is partly because no other generation has had a quarterlife crisis or graduated straight into such crippling debt — £12,700 on average and nearly £15,000 in London. No other generation has had so much choice or such great expectations. So we have become the experts on our own lives even when we expertly f*** them up. It’s just fine for your father to leave your mother for a motorbike half her age while she pursues her passion for home-shopping. But dare to share even a teensy bit of trauma and you’re slammed as self-indulgent. Apparently, we don’t know how lucky we are.

Researching my book, I travelled the UK talking to twentysomethings. There were, undoubtedly, some whiners. And I did want to slap a few trustafarians. But, 200 conversations later, it was clear. The quarterlife crisis is real: getting and keeping it together has never been harder.

Our twenties are not, as they were for our parents, ten years of tie-dye fun and quality me-time. Being twentysomething now is scary — fighting millions of other graduates for your first job, undergoing medical experiments to raise a mortgage deposit and finding time to juggle all your relationships.

We have the misfortune to be catapulted into a perilous property market. You will never have a home as big as the one you grew up in. The home your parents are secretly sucking equity from to fund painting holidays while you struggle to paint over the damp in your sixfigure studio flat.

Financially, the outlook is mixed. We’re earning more, and spending more, than ever. Now averaging £13,422 outside London, graduate salaries are great — even greater if you can find a graduate job. Gone are the days of raking in the bargain corner. No more dented tins. You’re off the breadline and on the focaccia line. It’s not easy, but it is easier.

That is partly because we use credit in ways our parents would never consider. Because we have to. For us, red is the new black — one in three callers to the National Debtline are now aged 25 to 30. Currently, I owe about £10,000 give or take £1,000. We’re getting into debt to finance our degrees, careers and accommodation. It’s not fun money. We need debt to live.

We are now also more likely to be depressed. The Depression Alliance says one in five adults is depressed at any time but it estimates that a third of twentysomethings have the doom. That didn’t used to be the case. Another cheery fact: suicide now accounts for a fifth of all deaths in this country by young people. That’s two twentysomethings a day.

Plenty of people are going to say the quarterlife crisis doesn’t exist. Let them. My father doesn’t believe in it. But consider that it’s not so long ago that the menopause, the midlife crisis and other life-stage problems were dismissed as self-indulgent. We’re convinced everyone else is having more (and better) sex, doing more (and better) drugs and generally having more fun than we are. And maybe they are. Our parents certainly did. But you aren’t the only twentysomething who hasn’t bought a great house, snared a gorgeous partner, paid off hideous debts and landed a dream job. In reality, few of us have. Most are just as freaked out as you are that your twenties are bigger, scarier and harder than promised. It’s just that nobody really talks about it. Until now.

So . . . you don’t know what you’re doing or where you’re going or whether you should buy a flat, get a pension or go travelling. Who cares? You have the rest of your life to work that s*** out. The decisions we make now are incredibly important, but they’re rarely irreversible. In the meantime, I think I’ll get my hair cut. Just a little bit shorter. I can always grow it back.

An extract from Get It Together: Surviving Your Quarterlife Crisis, by Damian Barr, will be published in T2 on Monday. The book is published by Hodder at £10.99 and is available at Times Books First at £8.79 plus p&p on 0870 1608080; www.timesonline.co.uk/booksfirstbuy

FACT OR FICTION?

Does the “quarterlife crisis” really exist? Or is it just twentysomething whingeing? Argue it out with Damian Barr. E-mail him now. Answers online on Friday

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