I'm going to tell a girl I'm available a couple days after I told her I'd be busy.
Why are you freeing up time for her?
I only wanted to be nice to her, to cheer her up.
It is kind that you want to cheer her up. Just make sure that your feelings towards her are genuine.
I think my feelings are genuine towards her.
I'm sure she feels the same about you. You're doing the right thing by deciding to talk to your crush.