It will probably take at least a day, if not a few days for data to be collected and shown on Google Analytics. So give it some time and it should start showing you some useful information!
Also, you can control the range of dates it displays by clicking on the dates at the top right of the screen. (a drop down calendar should appear) The default only shows data for complete days, so if you only activated it today, it won't show anything unless you change that, or wait til tomorrow.
I love using Google Analytics not only to see how many people are visiting my hubs (or blogs/websites) but also where they are coming from, how long they are staying, what they are looking at etc etc.