Similar thing happened to me too. Except I didn't ask this one out. She was unresponsive over text/phone so I just let it go
A few weeks later she asked me out on some, "You seem like a nice guy and I didn't give you a fair chance"

(When in reality, her no.1 option at the time probably fell through for whatever reason)
I took her up on the offer and we dated for 3 months. After which point she was like, "I'm really glad I went back for you. I was so close to missing out on a great guy. I really want something stable with us"
Told her I wasn't ready for a relationship though and it went downhill from there.