A 'shit22' is similar to a catch22 situation but in which things are far far worse than anyone could imagine.
In essence, a predicament that you would never, ever wish to find yourself in but people like Paul McCartney, John Leslie, Angus Deaton, Gordon Ramsey and Prince Harry keep finding themselves in.
When your wife says she's leaving you halfway through giving her a damn good seeing to and actually thinking of her.
An 'Oh my shitting christ!' moment.
1:) The feeling the dinosaurs had when they saw their friends being vaporised by a shock wave.
2:) When Ginny tells Harry Potter that she's up the duff
3:) Mallory & Irvine's joint feeling at having realised they had forgotten to climb back down.
4:) When Britney realises she's running after K-Fed's car in the nude with half an ounce of coke on her face...a 'shit22'
5:) When Kerry Katona was shown a tape of herself giving herself a Gynaecological examination after coming out of the bath.