Need help with amazing girl. Is she interested, or being nice?

I really like this girl from two of my cles. She is smart and pretty, and one of the most amazing people I have ever met. I can't stop thinking about her. She is a senior and I am a junior in high school. She is fairly shy, and we talk a lot during our last hour cl. Recently, I recomended a new hair style to her, she normally wears her hair straight down, and I recomended that she pull it back. She responded in a way that made me think she was uncomfortable, so I came to cl the next day prepared to apologize. I was shocked to see her hair pulled back, since then, she usually has her hair straight until our cl together, where it is pulled back again. I commented on it, and she mumbled something about the reason being her sweater. I recently asked her if she liked haunted houses, and she said she had never been to one, I asked if she didn't like to get scared, she said she did. So I invited her to a haunted house with someone from our cl and someone from my old school, she said she was really busy. I asked her if she really wanted to go, or if she was just trying to be nice and not hurt my feelings. She smiled and said that I was giving her loaded questions, and after a little more prying on my part, she smiled at me and said that she might want to go, but she was just too busy this weekend. I'm not really good looking, and haven't had good experiences with women, and only recently have I gotten enough confidence to start talking to more people and being more social, but I am so infatuated with her, that I can't help but talk to her. So I have two questions that I need answered: 1. Is she interested, or was she just trying to not hurt my feelings? 2. Since she has never been to a haunted house before and the haunted house closes next weekend, should I ask if she wants to go this coming weekend. and if yes, should I ask her to go with just me, or with friends again? Sorry for the long post, but I umed that the more information I gave, the better answers I would get.