People with multiple herniated discs, "pinched nerves", etc never have back pain yet people with no structural abnormality suffer from paralyzing pains.
The reason is your mind. The logic being your brain tries to hide difficult emotions aka stress and most specifically repressed anger (which you may be even unaware off) by creating physical pain by creating oxygen deprevation in some nerves (which is totally harmless like a cramp but feels like the end of the world to you).
So the pain is real and measurable even though harmless. Regardless, this creates fear and you start believing that the problem in your disc bulge, herniation, etc which is causing it. This is my own interpretation but it's the fear of pain more than pain that makes it into a debilitating pain.
Once you add all the advice on sitting like this and standing like that and getting into the car like this plus problems from your MRI, X Ray and more and more things you are doing wrong, you start believing there is something actually very wrong with you. Yet is not the cause of it but just your repressed emotions.
So long story short as soon as you start believing your body is fine and it your emotions causing the pain, the pain loses its purpose and goes away (that's why people who have been struggling for years get better in 2 to 3 weeks).
The best part is you don't even have to fix the emotions, Just knowing your issue is not structural will make you better.