i never played for large amounts because I never had the money to bet high.
but if you want to talk about pressure when i was 15-16 years old i already played pretty good and i would play adult men with no money in my pocket.
Try shooting a hard 9 ball when it's hill hill and your pocket has nothing but lint in it.
Talk about playing for lots of money when you were young, I played a black guy called Youngblood when I was around 15 and working in a pool hall. I lost about $500 playing him 9-ball on a snooker table using the balls from a regular table.
He was slamming the balls in HARD and they weren't popping out. He didn't beat me every game, but I think he had an advantage. That was the first time I'd ever tried playing 9-ball on a snooker table.