retired or tired? -- old and woreout or just old?

Im 64, Yeah I know, Im a youngster.
Lucky, Im in Good Health. My problem is that I still think as if I am in my 30's, that I can do Almost anything ! Bumping into things when I was young, I flinched, no problem. Now, its painful and I bruise. Just crawling under and back out from under my Dart is an affair. I have to roll Over onto my stomach, get on my knees, use one lege at a time to stand up. I have sworn off anymore Complete car rebuild.. it will be turn key. If I really like the car, i would consider doing an engine, trans, or Rear axle.
As they say, "youre not a Spring chicken anymore" and. " the old gay mare Ain't what she used to be"