If you think that your 15-year-old self would have sniffed at your mildew-ridden box room and the recruitment job you secured via a dodgy-sounding LinkedIn message, then stop your self-flagellation.
Not everyone is an Emma Watson or a Harry Styles, and that's okay. These super-successful musicians, actors, writers and businesspeople weren't household names in their early 20s either.
1 J.K. Rowling
At 21, J.K. Rowling had just graduated from the University of Exeter and was working for Amnesty International. But, at 28, Rowling split with her husband who she was living with in Portugal, where they met when she was teaching English as a foreign language.
2 Olly Murs
Before auditioning for the 2009 X Factor, Olly was working as a recruitment consultant in Witham, Essex. Now 32, he's had four number one singles, three number one albums and presented the X Factor.
3 Matt Groening
The Simpsons' creator moved to LA to pursue a career in writing at 23 but, at first, he worked as a chauffeur, biographer and personal assistant to a 93-year-old film director who, in Groening's words, "didn't have much of a career". Groening has compared his relationship with the filmmaker to Mr Burns and Mr Smithers. Eek.
4 Jay Z
Jay Z never graduated from his Brooklyn high school and he sold CDs out of his car before securing his first record deal. The rapper's debut album, Reasonable Doubt, was released in June 1996 when he was 26.
5 Ellen DeGeneres
Ellen dropped out of the University of Orleans after just one semester and her early jobs included waitressing at TGI Friday and working as a vacuum cleaner sales person.
At 24, she went on a not-so-glamorous stand-up tour of small bars and clubs around the US. She told W magazine: "There's lots of travelling, lots of being by yourself, lots of really rude drunk people. You're not just in big cities; you're in small towns, mini malls, strip malls... lots of places where, literally, the soup of the day got top billing. There would be a chalkboard on the sidewalk and it would say: SOUP OF THE DAY: BROCCOLI. AND ELLEN DEGENERES."
6 Iain Banks
Iain Banks wrote his first novel at 16 but did not publish his debut book, The Wasp Factory, until he was 30.
After graduating from the University of Stirling, Banks did a succession of short-term jobs that allowed him to focus on his writing. These included: clerk at IBM in Greenock, Scotland, testing technician for British Steel at Nigg Bay, Invergordon, and, later, a job in a Chancery Lane law firm.
7 Jeremy Kyle
Before working in radio and, of course, setting the world to rights, Jeremy Kyle spent almost ten years working in sales. After leaving uni, Kyle worked as a sales person until he was 30 before getting his first media job as an evening radio presenter on Kent's Invicta FM.
8 Colonel Sanders
Long before he became the chicken mogul you know and love today, Colonel Sanders (or Harland David Sanders, as he was known pre-colonelhood) lived a difficult and dangerous life.
Before he even reached his 20s, Sanders had already worked as a blacksmiths helper, cleaned the ash pans of trains and faked his age to join the army at 16.
While studying law via distance learning, Sanders worked as a fireman but lost his job for brawling with a colleague. Sanders was then dismissed from his first job in law for brawling with his own client in court. He was also fired from a job selling life insurance before establishing a ferry company and working at the Chamber of Commerce.
Sanders, who was born in 1890, didn't start serving chicken for a living until 1930. And, unfortunately, the chicken business in those days wasn't all orderly queues and hairnets. Sanders was involved in a shootout with a competitor in which his opponent killed a Shell official, resulting in a murder conviction that took him out of the chicken game, and out of the Colonel's way. Sanders didn't franchise Kentucky Fried Chicken for the first time until 1952, when he was in his 60s.
9 Jason Statham
The action star didn't actually appear in his first film, Lock, Stock and Two Smoking Barrels, until he was 31. Before that, he was part of Britain's national diving squad for twelve years and, at 22, even competed in the 1990 Commonwealth Games (see video below).
While he was training, Statham was scouted as a model but he still struggled for money and sold fake jewellery and perfume on the street to keep himself afloat. While modelling for French Connection, Statham was introduced to director Guy Ritchie, who cast him in Lock, Stock and Two Smoking Barrels.
10 Malorie Blackman
The Noughts and Crosses author worked as a systems programmer, receptionist, catering assistant and shop assistant before she began writing full-time.
Blackman's first book was published in 1990, when she was 28, and Noughts and Crosses was not published until 2001.
11 Brendan Gleeson
The Harry Potter actor, who plays Alastor 'Mad-Eye' Moody, was a secondary school teacher for ten years before he started acting at 34.
Feature image: Warner Bros/ iStock/ Matt Groening/ Bibliodaze