Probably stupid question

I am pretty useless at working out what women think. (But who isn't?)

Started college about a month ago, this girl that I'm starting to quite like who I hang out with with another dude (who's in his own relationship with someone else) randomly asked me (the girl asked me not the dude) at lunch time if I was still annoyed at her about something. I dismissed it pretty quickly, and asked what she thought I'd been upset about.

The back story is we had a political debate last week which we basically completely didn't agree on, but we'd been joking about it for days since.

She dismissed it as not about that, and claimed she can't remember what it was about and we seemed to get on fine for the rest of the day...(although I did accidentally imply she may be stupid by "not commenting" on something she said, but I think it was mutually joked off.)

But I won't see her until Thursday, I kind of want to get to the bottom of what she was on about. I am far better at talking about this stuff through texting or 1 to 1, rather than around the other dude.

Should I try and talk to her, or just leave it and see her Thursday as normal?