Don't worry about age John.. If your health is OK you've got a few years yet. I am 78 and still "at it". New KN7000 this year with amps and speakers which I lug around unaided. Yesterday I did a 6 hour gig with just a 10 minute break for food and enjoyed every minute of it, at least until the voice started to get a bit croaky.
What now seems like a lifetime ago when I was playing with bands, I remember saying that I couldn't see myself still playing at 60. Then that went to 65, then 70. Now I have stopped that line of thought altogether. When the grim reaper comes
for me I'll go, taking my KN7000 (or whatever I'm using then) with me.. I just hope the money's good down there.
Take care of youself
Trevor