A senility rhyme for second childishness

On entering what Shakespeare describes as "second childishness", all sorts of little aches and pains begin to manifest themselves. It's easier to put on weight and harder to lose it. You don't sleep so well. Oh, yes, and although you can remember things from your childhood, you have no idea what you were doing yesterday.

So here's a silly senility rhyme for anyone having trouble remembering how to count:

One, two, Can't reach my shoe;
Three, four, My knees are sore;
Five, six, Mem'ry plays tricks;
Seven, eight, Putting on weight;
Nine, ten, Remember when?
Eleven, twelve, Projects shelved;
Thirteen, fourteen, Cutting down caffeine;
Fifteen, sixteen, When's my flu vaccine?
Seventeen, eighteen, Now I am unseen;
Nineteen, twenty, Must spend a penny.

More stuff

• Image source: Wikimedia Commons: Joachim Martin Falbe
• Nursery rhyme inspiration: Wikipedia: One, Two, Buckle My Shoe