I love the 24 hour clock and living in London, UK I used it all the time. However, I remember one time I bought movie tickets at lunch for 17:30 and my brain thought it was for 7:30pm and I called my friend at the last moment saying: “you have to leave work early if we’re gonna make it!”
Go for a walk in the mornings if a run is too daunting. Gradually go up.
A problem I had is I’m too dedicated to some things and will run a lot and then injure myself by going too often or beyond what my body is capable of instead of ramping up in a healthy way. Then I wind up doing nothing again due to injury.