For me over-analysing and over-thinking is a form of procrastination and a way to continue avoidance. If I am "busy" playing in my psyche, I can overlook other areas or even avoid them entirely. Mindfulness is what I use to to stay engaged in whatever I'm already doing and try to experience something more positive like contentment, pleasure, play, satisfaction, comfortable, even at times just "okay". But before I try to be mindful about something, I have to make a consicous decision to stop contemplating my navel and get up and attempt to DO something, even if it may be uncomfortable and cause some anxiety... for a time (a friend I know sets an egg timer and she does it for 10 minutes and when she hears the "ding" she reevaluates it and most often chooses to stay engaged in the activity).
It was hard at first, but it is getting easier with practice.
Came back to add my own personal benchmark... an old Jethro Tull lyric "there's no time for everything". If I keep this in mind when I plan my day... I can do some self examination and reflection for a time. But I also set up my schedule for other things, like self care, exercise, social/fellowship, housework, and even though I really don't want to I have a small part time job and I can shift my focus to that and shut down some of the self reflection (which was chronic and kept me isolating and depressed). It was really hard at first, but over time and with patience, persistence and practice, it is getting easier though still mild to moderately uncomfortable.