I was 29 in January 1984, so almost exactly 37 years ago. If math still works the same way now, that makes me 66. Only 600 years to go, and I'll have you all worried!
That day sticks out in my head, as in the morning my family held the funeral for my paternal grandmother, who made it to age 97, and in the afternoon I sat down to roll the polyhedral dice for the first time. Spent part of the session using a crayon to fill in numbers on the dice. That's kind of equivalent to cuneiform on clay tablets ...
Some years later, I was talking with a co-worker. Her son was only 5 years old when he first played D&D. I believe he's in his 40s now, and a few years ago I learned he's currently working at Google.
I must confess that I am green with envy of all of you who started playing when you were kids! <mutter-mutter, grumble-grumble> LOL