Lance had deliberately brought up last semester's incident, probably to make her misinterpret his words on purpose.

If Bettie directly corrected Lance, it would seem as though she had been dwelling on their past encounters.

"Isn't it summer at the moment? What's running through your head?"

Bettie shot back with confidence.

With that, she turned and kept walking. "I won't discuss this further. Let's move on."