Buy low, sell high. That tired mantra was surely rattling around the brains of plenty of investors who saw opportunity in the whipsawing U.S. capital markets this week. Some brave amateur day-traders even dared to wade in amid the volatility. What could possibly go wrong?

Buying Monday’s rapid sell-off didn’t end well for one 24-year-old financial analyst in Vancouver who wound up losing his entire savings, and then some -- about $10,000 in total.

He’d been dabbling in the stock market since July, and managed to pocket as much as $2,500, literally overnight, by spotting dips, then selling as indices roared to fresh record highs. He said he repeated that sort of return a few times, lavished money on his friends, and splurged on six electric guitars, a drum kit, amplifiers, music festivals, thousands of vinyl records, and of course a stereo system.

When he noticed the Dow Jones Industrial Average plunging on Monday, a sell-off that would go down as the biggest daily point loss of all time for the basket of 30 major U.S. companies, he couldn’t resist. He fired up an app on his phone while at work, and started placing orders through his broker.

He transferred $4,000 into his trading account and started buying CFDs (contract for difference), tradable instruments often used to speculate on the direction of the market. It’s basically an agreement between a buyer and seller to exchange the difference in value of an underlying asset between when the contract opens and closes. The investor never actually owns the underlying asset. In this case, the value fell -- a lot.

“I was mainly buying CFDs for the NASDAQ 100, Dow Jones and Google,†the investor, whose name is being withheld by CTVNews.ca, said in a phone interview. “I knew it would go down further, but I didn’t expect it to be that bad.â€

He got margin called a few times, meaning his broker insisted he put up more money to meet minimum requirements. He ended up using his credit card to help stay in the game longer, investing a total of $10,000. It wasn’t enough.

“My broker closed it because they didn’t have money,†he said. “So I couldn’t ride the rebound. It was too late.â€

He struggled to concentrate for the rest of the workday, receiving minimal empathy from the coworkers he confided in.

“I f***ed up. I'm depressed,†he posted on a personal finance forum under the username aesthetic_manlet. “I've made money in the past catching these dips. Except today it's not just a dip. The market is continually crashing. And it all happened so fast.â€

In the post, he lamented telling his parents and pondered how he would pay for tuition to earn his accounting designation, his auto insurance, and the mortgage he shares with his dad. He briefly considered taking another run at the market to recoup his losses, but thought better of it.

“It’s basically gambling,†he said. “So ya, I didn’t do anything.â€

The internet was surprisingly kind to the young investor. A few fellow Reddit users were appalled by the idea of buying leveraged investments with credit card debt, but most offered reassurance, advice and tales of their own financial failures.

“You learned an important lesson today. If you want to trade, that's fine, but don't ever do it with money you can't afford to lose,†wrote user np20412. “If you’re going to trade on margin, don't ever do it with more money than you have sitting in cash or easily liquidated stable investments.â€

User Goodman1988 found the candid admission refreshing.

“We need more stories like this to show the reality: the only financially responsible move on the stock market is to invest on the long-term and well-diversified,†he wrote. “I hope other people that are still under the impression that the stock market offers great returns on the short-term read this story, as well and also learn a lesson. People like to brag about their successes, but when their luck runs out they go silent.â€

He is still licking his wounds, and figuring out how to get out of debt. So far, he said he’s sold the $3,100 in stock he had in a separate account to help pare down the more than $6,000 still on his credit card.

While the parental backlash wasn’t as bad as he anticipated, he sort of grounded himself briefly.

“I actually had plans on Monday. I was going to meet up with my friends, but I cancelled on them. One, because I don’t have money. Two, I don’t feel like driving on the highway. I might get in an accident if I think about stocks,†he joked.

At 24-years-old, he realizes time is on his side when it comes to recouping this loss. But he said he plans to take this experience to heart, and avoid swimming with Wall Street sharks armed with instant information to help them navigate turbulent markets. Now, closely managed mutual funds are his new preferred speed.

“You always win (in) the long-term. You can gamble, but do it with money you can afford to lose,†he said. “And don’t ever trade with your credit card. That’s not a wise thing to do.â€