Twitter poppedl; the rest of the market dropped. Twitter wowed investors with a 73% surge on its first day of trading. The broader market, though, had its worst day since August on worries the Fed will cut back its economic stimulus — even as soon as next month — thanks to a surprisingly strong report on third-quarter economic growth. After 33 record-high closes this year, more and more investors say the stock market has become frothy and is ready for a pullback. ‘The market had rallied a heck of a lot, and to justify further gains we really need to see the economy improving or corporate earnings picking up,’ said Alec Young of S&P Capital IQ.