When the market gapped up in the morning yesterday, it was up around 13% in just matter of few days. That kind of move was invitation for profit taking. Market gave up part of the gain. Market will likely take some time to build on its reversal.
This is a big week for earnings and number of large caps are scheduled to announce their earnings this week. Investors would be closely looking at the earnings and earnings projections for clues. Earnings season tend to be volatile. Lot of bad news has already been priced in to the market and so bad earnings or bad guidance will not come as a surprise in many cases.