With Uber Technologies Inc.'s shares plunging nearly 20% below its IPO price on Monday, the stock might be fast approaching a "white knuckle" territory, according to one Wall Street analyst.

After closing down 7.6% on Friday in its trading debut, Uber's stock dropped as much as 13% on Monday in New York, before closing down 11% at $37.10. The initial public offering was priced at $45.

"From a stock perspective, if Uber breaks $35, that is where it starts to get even more white knuckles," Wedbush analyst Daniel Ives said in a phone interview. "Right now the bears are winning, and there is nothing to stop these stocks from moving down, especially in a risk-off environment," the analyst added, noting the weakness in ride-sharing peer Lyft Inc., which is also down as much as 7.3%.