Hi Arjun,
You should just leave it.
Your crush is used to receiving a certain amount of attention from you. When she didn’t get it for those few days, she became needy.
Hence the reason why she sent you the text asking you about why you didn’t text her to see whether she was okay.
A girl can still want attention from a guy that she isn’t romantically interested in.
Thereby, try to avoid thinking that she sent you this text because she is interested in you. You already asked her to be your girlfriend and she rejected you.
You should stop looking at her as a romantic prospect and focus your attention on other girls. If she has truly had a change of heart and wants to be with you romantically, the onus is on her to make that move, not on you.