Stock prices doesn't depend just on company performance. It also depends on market sentiments and news can make the share prices dip. Just look at alibaba.
Facebook dropped nearly 5% after the worst outage and whistleblower interview
Stocks go through peaks and troughs.... they don't move in a straight line chart.... thus, today may be one of the troughs along the way.... dont be too worried... sunny days will come around again soon, if there are no bad news on the horizons.