whizzing towards the grave

Geoffrey and I were enjoying a pipe of Black Bogey and a glass of madeira by a crackling fire of driftwood - and the bits left over after we rebuilt the rocky outcrop - when we began reflecting on our years together as best friends.
"Why is it," asked Geoffrey," that as you get older, time goes faster?"
"I know exactly what you mean, Geoffrey. But I don't think it does. I think perhaps it only seems to go faster."
"No, there's more to it than that. Sometimes I feel I'm whizzing towards the grave. And I certainly didn't feel like that when I was young. When I look back and recall my childhood years, it seems like summers were always sunny and lasted for ever. Remember when we used to steal apples from Grandad Tupfinder's orchard, and scull across the bay in your coracle with the sun on our backs? These summer days seemed to last forever. Even the winters were properly snowy, the stars were brighter and it took an age for Christmas to arrive."
"Of course I remember these things, Geoffrey. We're just getting old. There's nothing more to it than sheer nostalgia. No need to get over-sentimental about it."
Geoffrey fluffed up his feathers huffily. "No need to be insulting, either Tuppy. I WAS going to tell you my theory about time, but I shan't bother now."
"I'm sorry Geoffrey. I didn't mean to upset you. I'd love to hear your theory about time. Look, have a packet of crisps. I've got some doritos in the sideboard."
"No, I'm giving up crisps for the new year. They're bad for my blood pressure. Far too salty."
I gasped. Geoffrey, giving up crisps? and worrying about his blood pressure?
"Geoffrey, please. Time is passing so quickly - or seems to be - that we might as well enjoy ourselves while we can. What's this nonsense about crisps? Next you'll be giving up tobacco and madeira!"
"I know, Tuppy. But all this thinking about time has got me in a panic. And I got a bowel cancer testing kit through the post the other day."
"Who on earth sent you that? don't tell me - Tuppence, up to his tricks again, trying to frighten people!"
"No, Tuppy. It's Dr Wilson. He says we've all to get it done, for our own goods."
"For our own goods? What kind of horsecrap is that?" I should have known that Wilson was behind it. I got to my feet and began to pace up and down the room, the peaceful atmosphere shattered. This wouldn't do, at all.
"Come on Geoffrey. Snap out of it. Think about your time theory, not bowel cancer. We've all got to die some time. Let's go out with a bang." And I brandished a pack of Chilli Heatwave flavour doritos.
"N-n-n-no! You're trying to kill me!" Geoffrey stood up and backed away, towards the door.