There's a version of Izzy who didn't go down to Bureau to dispute her results and simply would've accepted what was given. She very nearly didn't get up that morning. And that's the sort of Izzy who didn't ask around about going home.  

To protect herself from wasting time or disappointment, Izzy has preemptively stopped herself from doing a lot of stuff. She can't really dwell on it. But it does bother her sometimes. It's that bit of bother that pushed her to get up that morning an argue her case. Though there's something else that's been bothering her more lately.