I think you might have had temporary pain that created a bad position and a lack of flexibility (the words I want to use are typically the words I don't know in English, sorry if I'm not accurate, I try).

The same thing happened to my left ankle. A double sprain (both tear) made me walk with an angle and a locked feet for years, which didn't help with rehab at all and caused pain (because I was locking it in uncomfortable positions). Part of it was psychosomatic: like you said, expectation of pain, most of it was real pain caused by myself.

Also I stopped doing sport, kept eating the same, became fat and changed carrier towards CS, because clearly I couldn't keep working my jobs without the ability to run.

So definitely not as simple as you made it to be but true enough that this can be good advice to people with chronic pain.