She could have been interested. However, you more than likely walked away when she said that or got angry. A confident man would have been nonreactive to her little comment and teased her. Saying things like "get lost" might have been her way to separate the good from the bad.
A few ways you can tell if a girl likes you is if she keeps looking at you from across the bar or if she gets really close to you. Sometimes girls will get close hoping that you will open them. When you are talking to a particular girl and she is touching you a lot,touching her hair, leaning into you (all of these being IOI's) then she is interested.
You should have responded with: "Thanks but I already have all seasons of Lost on DVD"
