I retired about 18 months ago although it was phased in that I went part-time several years before that and then worked from home during Lockdown. The transition was therefore not as sudden as yours perhaps. However, shortly after retiring and after working for 48 years I found myself looking for jobs online without any intention of applying for them.
I now feel a tad guilty in that I can live better than most people in the world merely by getting up in the morning but life is great if you have your health. In fact,you have the opportunity to get fitter than you were in a sedentary job.
I walk, attend classes, socialise a lot more,attend footy games and travel a lot more. Can't remember being happier away from the pressures and frustrations of work and time is a wonderful gift.