"The semiconductor index was down even more than the biotech index, and to me that's just as important, if not more important, than the biotech space," said Ian Winer, head of equity trading at Wedbush Securities. "Semiconductors tend to be a leading indicator for the economy. If you see issues with semiconductors, you'll see issues across the economy."
The Nasdaq Biotechnology index is down 0.46% today, while the Philadelphia Semiconductor index is lower by 1.42%.
"I don't see any panic with biotech," he said. "You can construe that as positive or negative, but I don't get the sense that it's over. Investors were just cutting their exposure."
As for what's ahead, Winer sees the markets following the dollar's lead going forward, as a strong dollar has prompted analysts to predict negative earnings growth for the first quarter. If the projected declines come to fruition, the upcoming earnings season would be the first quarterly drop since the third quarter of 2012, according to FactSet.
Meanwhile, investors are also watching the steep rise in capital moving into corporate bonds, potentially posing a threat to stocks.
Investment-grade and junk rated companies sold $438 billion in bonds so far this year, compared to $384 billion at this time last year, according to Dealogic data cited in The Wall Street Journal.
"Companies have been altering their capital structure because rates are so low thanks to the Fed," Winer added. "They're selling debt and using those proceeds to buy stock and that has brought in a lot of supply and added support to the market. That's one of the things the Fed has done that people don't talk about."
Winer doesn't think the Fed's possible tightening later in 2015 will stifle demand for corporate bonds. Yields and prices move in opposite directions. Plus, the Fed's liftoff will likely be in small, 25-basis point increments.