Is there a minimum reputation necessary before you can see the graph? If so how long does it take to update the graph? Because I've never been able to see mine on my Stack Exchange user account. All I see is a white box.
Only sites on which you have at least 200 reputation will be shown, and the graph is only updated once per day (sometime after UTC midnight). It looks like you just passed the 200 reputation barrier on Jewish Life and Learning (and Stack Overflow, thanks to the association bonus), so your graph should appear sometime in the next few hours.