Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What's happening: Shares of Tile Shop Holdings (NASDAQ:TTS) were up 16% as of 11 a.m. Tuesday after the company announced better-than-expected first-quarter results.

Quarterly net sales rose 13.3% year over year to $73 million, helped by a combination of new locations and a 4.5% increase in comparable-store sales. That translated to a 10% decline in adjusted net income to just under $4 million, or $0.08 per diluted share. Wall Street would have been happy with earnings of just $0.07 per share on sales of $70.7 million.

As if that wasn't enough, Tile Shop also reaffirmed its encouraging full-year guidance, which you might recall was the source of another post-earnings pop in February. For reference, that guidance calls for net sales of $275 million to $290 million, eight to 10 new stores, comparable-store sales growth in the "low single digits," and adjusted earnings per share of $0.27 to $0.33. Analysts, on average, were modeling 2015 adjusted earnings of $0.29 per share on sales of $282.5 million.

Why it's happening: Tile Shop CEO Chris Homeister touted "solid early returns on our key initiatives," then elaborated: "Positive comparable store sales growth, continued gross margin strength, working capital management, strong operating cash flow, improvement in key talent metrics and sound expense control all contributed to strong bottom line results in the quarter."

In the end, it may make investors slightly nervous knowing shares of Tile Shop are up 65% so far in 2015, but keep in mind that after last year's struggles the stock has only clawed its way back to where it stood almost exactly one year ago. As long as Tile Shop can continue delivering on its key initiatives, I see no reason Tile Shop stock can't continue to rise.