Continuity mistake: Carrie opens the safe to take out her gun. The safe is closed when they take her with a hood. When Quin comes in the safe is open again.
Continuity mistake: Saul, Dar and Lockhardt leave Saul's office and walk through an open door into the adjacent conference room. The connecting door remains open but in the next shot the door is now closed, enabling Saul to lock the senator in the conference room.
Factual error: As Brody is driven away from the square after meeting Abu Nazir's widow, the shot from inside his car reveals a public telephone box on the corner. He is supposed to be in Tehran, Iran - however the distinctive colours of the phone box are those of Morocco (where I assume the scene was shot). (00:35:40)
Continuity mistake: When Brody is captured in the previous episode his head is completely shaved. This episode takes place no more than a few days later (it is actually implied that it is three days), but he now has a full head of hair.
Continuity mistake: When Carrie is talking to Brody from across the room, her hair jumps several times between being tucked behind her ear to hanging down by her face. (00:20:30)
Continuity mistake: Shortly after halfway through the episode, Carrie Matthews discusses the fate of her unborn child with her sister and father. Her hair is not tucked behind her ears - then it quickly is.
Chosen answer: Everyone else calls him Brody or Sgt. Brody, and it probably became habit to her.
The_Iceman
Can't get the source but I read that even the Producer responded to that. Stating that it was common practise for a military wife living in a military complex as everybody refers to their husband by their last name.