Even with the "rebound rally" seemingly in full force, CNBC's Jim Cramer doesn't think it's time to get comfortable just yet.

"Look, I'm not saying we can't keep rallying here, ... but here's what worries me: what if all we do is hold, then bounce, then sell-off again before yet another retest of the lows?" the "Mad Money" host said. "Just because we made it out of the woods of Monday and then yesterday, doesn't mean it's going to be smooth sailing."

On Thursday, Cramer set off to find the top risks that could throw a wrench in the rebound.

Among them were an excessively strong nonfarm payroll report from the Labor Department; another errant tweet from President Donald Trump, who no longer seems to judge his success by the market's performance; the snowballing tariff conflict between the United States and China; and the president's push to renegotiate NAFTA.

But one of Cramer's biggest concerns was that FANG, his acronym for the stocks of Facebook, Amazon, Netflix and Google, now Alphabet, has become an entirely new "wild card" in light of "the president's tremendous onslaught against Amazon."

In the last week, Trump has targeted Amazon in five separate tweets, criticizing the online retailer for its tax treatment and its deal with the United States Post Office.

"Right now he wants to rip up Amazon's contract with the Post Office to get a better deal, ... as he regards this company as a destroyer of mom-and-pop retailers across America," Cramer said.

In his string of tweets, Trump argued that Amazon was costing taxpayers "billions of dollars" for using the Post Office as its "delivery boy."

"More important, [Trump's] naked antipathy for Amazon's CEO, Jeff Bezos, could be a real problem," Cramer added. "Bezos owns the Washington Post, which the president believes is out to get him, and I worry that he'll stop at nothing to humble its owner."

Cramer told viewers on Thursday that he found Trump's arguments "pretty specious." The Post Office negotiated its contract with Amazon, and while it may have accepted a lower price, the contract provides income that can be used to subsidize first-class mail, Cramer said.

"However, you don't need to be a huge cynic to believe that this is all about punishing Bezos and the president's good for a negative tweet about Amazon pretty much every single day," the "Mad Money" host said.

Cramer saw this one-sided war on Amazon as a big problem for the market given FANG's almost overbearing influence on stocks.

Every time Trump tweets an attack on Amazon, its stock and the rest of FANG tend to drag down the exchange-traded funds and the major averages that include them, Cramer said.

"So as much as I would love to sound an 'all clear,' there are too many potential pitfalls. What about that too-hot employment number? What about a president who no longer seems to care that much about how the stock market's doing? What about FANG risk and Chinese retaliation? What about NAFTA? You scrap that, I think you could kill the bull," Cramer said

"Bottom line: don't be so quick to call this rebound a 'tradeable bottom,'" the "Mad Money" host said. "If things go the wrong way, it could become an un-tradeable non-bottom pretty quick. That's why I'm counseling caution."