It might very well be the car of the future but the past few days have seen Tesla turn into an old-fashioned rollercoaster.

A story in Monday’s Wall Street Journal said Tesla sold 26 percent fewer cars so far in 2014 than in 2013. That caused a huge selloff in the stock—and led CEO Elon Musk to go on Twitter to defend his company, saying:

“Article in @WSJ re Tesla sales is incorrect. September was a record high WW and up 65% year-over-year in North America.”

By Tuesday, the stock recouped its Monday losses and then some.

(In a followup, the Journal stood by its report, noting that its original story was about year-to-date numbers while Musk was talking about the month of September only.)

Uncertainty over Tesla’s sales may have hurt the stock. But any drop in sales may have been more about Tesla’s ability to get supplies of its electric cars to market rather than the demand for them, according to CNBC contributor Gina Sanchez, founder of Chantico Global.

“It’s not like sales are falling because people aren’t interested,” she said. “People love this car. People want this car. They just have trouble meeting demand.”

In the meantime, Sanchez believes Tesla’s stock is overvalued, hence the wild swing this week. “It really is priced to perfection,” she said. “Any bad news is going to shake the stock.”

But demand for Tesla shares may be another matter. While the stock may now be back above its 200-day moving average, the technicals could be signaling trouble ahead.

Ari Wald, head of technical analysis at Oppenheimer & Co., doesn’t think Tesla will continue to bounce higher. What worries him about Tesla is that it wasn’t able to sustain a breakout above resistance at $265 per share in September.

“That gives us some clues that there really isn’t a lot of conviction in buying demand for this stock,” he said. What’s more, Wald sees a warning in an indicator that tracks momentum. (It’s called the moving average convergence/divergence indicator.)

“Since last year at this time, the stock has been making these higher highs but momentum has been making lower highs,” he said. “Momentum has been fading through its rally.”

Wald recommends investors sell Tesla shares as it heads into resistance around $250. “I would sell it there,” he said. “There’s risk it could still set back to $180 support.”