I would’ve slightly changed your response to actually directly ask her when she’s free instead of relying on her to let you know you at some later point. If you get what I’m saying? Now you’d be waiting for her to hopefully remember or get back to you.

“No worries. What’s your schedule like this week?”

You jumped on the reschedule too quickly. And you accepted the flake happy go lucky

"Oh gotcha... "Maybe" another time?"

And then get her concern out if any