I'm one of those too. Work harder than anyone I know, always have my whole life. But I turned 40 this year and start to feel the effects. 

Four years ago I threw out my back for the first time, and although it slowly healed over following few weeks, it was never the same. At the end of 2023 our farming season went well into November and my back had been getting progressively worse again, but I wouldn't let up, there was too much that needed to be done. Ended up that the very last week of the season saw me flat on my back completely unable to move.

39 years old and I couldn't get out of bed, couldn't get dressed without assistance. Spent weeks and 1000s of dollars at the chiropractor and took almost three months to recover... That's when it became real to me that my back wasn't going to last forever and if I kept working like this I was not going to make it very long, and also that it would cost me so much else that I enjoy doing.

Wishing you a speedy recovery. Aside from the pain, I found the frustration and helplessness of not being able to do what you want or need to absolutely excruciating. Not a good feeling at all. Hope it passes quickly. 

 You sound very young to be suffering like that. Need to put your brains before brawn now. 

As you say, it's the mental adjustments that are hardest. As a species we can be a bit dim accepting limitations.

 What I didn't realise is that your head is connected to your back.

I used to break down physically every 2-3 months, spend 2 weeks hobbling then feel physically fine and get back to doing too much, not realising the mental impact.

I don't recommend falling into that trap. 

Take care of yourself. Cheers