Ambiguously Asking for a Date

Date: 2/23/2019

I'm talking to a friend. She has blondish curly hair and glasses, and I don't know her very well. We're both going to a concert soon and she doesn't want to go alone. She asks if I want to go with her. I want to be nice so I tell her sure. Se says "see you there" and walks away before I can tell her I'm already going with my girlfriend.