My worst experience was years ago. I was wishing to stick a bet on at Glorious Goodwood summer meeting and it was my day off. 5 races on Ch4 on a week day. I had the day off but I had to attend a training course. I had my 5 horses marked out in me paper but I didn't have the time to stick the bet on (Always either a Canadian or a Yankee). That evening Ch4 showed highlights of the days meeting. All 5 won at odds ranging from 20-1 to something like 5-1.
I will never forget it
OUCH! - Neither would I, that would bloody haunt me until the day it was Game over lol.
Can tell a similar story, although not really gambling related but equally (ish) gutting.
At work one day, I had a £20 note, car was off road and needed change for bus.
Went to our reception where they paid out customer travel X's from and stored the petty cash and asked receptionist for some change...
"I've only got 0.20p's left Jon, all the notes and £1 coins have gone" she said.
"Not to worry I replied, they're only going in the bus anyway and for my lunch, I'll use em over the course of the week"
Returning to my desk, I opened one of the 2 x £10 bags I'd been given and as I separated £3 or £4 for lunch n bus fare, I noticed they'd got no date on them.
"Hey you lot" I said to my team "These new 20p's don't have a date", met with little reply, I put em in desk draw n some in pocket.
Proceeded to spend them all over the week, thought nothing of the missing date and didn't even keep one!
You can work out the rest lol - Over 5 years ago now that was and still bothers me to this day, more so when I see the coin related articles in papers pop up from time to time.