In Tesla's favor, revenue is way up, $401 million versus $22 million, and that does sound impressive. Based on the stock price, investors are expected 18 times growth going forward. Sorry, but growth trajectories that high are not sustainable. Investors also jumped with glee hearing Tesla delivered 5,150 cars, 650 above the expected production. Elon Musk is a fantastic CEO and Tesla has a waiting list for cars. What did you expect? You should anticipate another beat above the guidance of 5,000 cars reported for this quarter unless they run into production issues. Absent California Zero Emission Vehicle (ZEV) credits, Tesla has a long way to go to reach its stated 25% gross margin goal by the fourth quarter. Tesla also faces increased competition from General Motors ( GM), Ford ( F), Toyota ( TM), and others. If you're buying Tesla at the current $155 a share, just make sure you're close to a chair when the music stops. Tesla is loved for now, but the market is anything but faithful. At the time of publication the author was short AMZN.Follow @RobertWeinsteinThis article was written by an independent contributor, separate from TheStreet's regular news coverage.