I DIDN’T know I was old. My face has gone baggy, and my hair has sunk back through my scalp to reappear as wire in my eyebrows, ears and nose, but I don’t count any of that – I can still do more pull-ups than any of the 21 people in my family. But yes, I’m old. How? Why! It’s losing touch with the modern world that makes us old. I thought I’d signed up when I bought a mobile phone. But apparently you have to do more than just phone people and talk to them. So I learned to take photos, send texts (why do people laugh when I…