Girl is acting differently after I added her on Facebook?

OK, so I met a girl through a society at uni who I had a bit of chemistry with... and I added her on Facebook (mainly to see if she had a boyfriend or not) however when she accepted my request I noticed that she does. However, ever since the add she is getting into my personal space a lot more and can't stop looking me up and down. There has been a total change in her behavior and I don't know why?

Put the internet to work for you. via Personal Recipe 2629979