The camera tracker is unable to determine any depth information from your scene. This could either be because your shot has no parallax or because you manually choose Tripod Pan in the effect settings. A screenshot of the Effect Controls panel would help.
By the way, if you're just getting started with After Effects, you're starting at the wrong end. Working with trackers in 3D is advanced. I very strongly recommend that you start here to learn After Effects: http://adobe.ly/bjBT3P
As Todd said, your shot has no depth. There is no good perspective reference because it's a night shot and the most prominent features are the lights and windows which the tracker onbly perceives as isolated points, not part of a surface or edge. you will have to look into other tools that allow placing manual reference points, if that is critical to you.