Oh, she can hear that sarcasm, Optimus! She is an expert in sarcasm, and it's pretty funny, coming out of him.

"Well, I was bored with flying around the planet, so I came back here," she tells him, tone innocent and sweet (or as innocent and sweet as someone who sounds like Starscream can sound), "and then I came inside, and then I talked to one of the medics and hung around the back. That's what I was doing. What're you doing here?"