You haven't really mentioned how long you know this girl or how often you've spoken to her and spent time with her so I can't really say much. Are you able to answer this?
What I will say is this. I know someone who had met a girl at his cousin's 21st party and after about 2 weeks he told the girl that he was falling in love with her, Well 3 years later they are engaged to be married.
You need to think rationally and play your cards right. Just talk to her, get to know her. Infatuation/obsession is bad news.
I'm in a similar predicament actually. I met this girl last xmas so have only known her for just over 2 months. We've been out about 5 times for coffee, lunch, beach, movies etc. I made the mistake of telling her after a few weeks that I was fascinated by her and she said that we shouldn't talk for a while because she didn't want to lead me on. She said she didn't want to stop contact and I told her I still want to be friends.
She's from Brazil and will be leaving Australia in about 4 months and having been in several relationships in my life I am definately wanting to get to know her better and see where it leads. I want to see her more often but I can understand her position as her whole life is in another country.
Even though I have been in love and long term relationships in the past I am trying to decipher whether these feelings I have is infatuation or real. I know for a fact she doesn't feel the same way or otherwise we'd be seeing eachother more often and of course been physically closer towards eachother than just friends.