<human>: Give me a shortened version of the text

I met this girl a last week through an acquaintance, and spent a decent amount of time talking with her. She seemed nice enough, but also seemed to like me quite a bit more than I liked her. Then today, she asked me pretty much out of the blue (but not face to face) if I would like to come to a charity ball that is happening at the weekend. 

I asked her about it, and it sounded like we would probably be the only young people there. I don't know if this just means that she wants some company (which I am perfectly happy with) or if she was seeing it as a date. I didn't want to say no to her, so told her that I would be happy to go so long as I hadn't forgotten about something I was doing that evening. She seemed really happy about that... 

I then asked her how much the tickets were. They were way to much for me to be able to afford, so I told her that I might not be able to come - to which she immediately said that she would pay for my ticket - to which (after asking her if she was sure quite a few times) I said yes...
I don't know if I'm just over analysing the situation, but I really don't want to have led her on, and also wasted her money as well. Also, I'm from the UK, but I'm in the USA at the moment, so I'm not sure if things are just different here, and this is just a totally normal thing for friends to do. 

Any advice on this mess would be a huge help. Either a way to confirm it isn't a date (without actually asking her, because I'm still not totally sure it is a date) or to tell her that I can't come without making it sound as if I don't want to come because of her. Thanks people...
<bot>: I don't want what might be a date to be a date, but I don't want to upset her either.