Do ljbf responses always imply lack of interest?

I went on a date with this girl and messed up and got a LJBF response.

Using a suggestion here I replied no worries and followed it with another text saying sure as long as it's not just for social grace.

I can tell she hasn't gotten over her ex who is a coke "recovering" addict who cheated on her while they were on vacation. Blah blah blah..

I don't show her the same interest when I see her but I will talk to her and casually look at other attractive girls in class. Just by not being phased by her response; not moving my seat, and overall just taking the rejection well + interest shown by other girls; she wants to see me again..

Was this a shit test?

My guess, is I should cancel plans last minute to reestablish frame. Any other ideas?