If you want to know if someone likes you, check these out. Displays of interest. Such as laugh. I'm assuming your a guy so, when you say something, be it not even really funny she will still laugh. Proximity. She will always try standing close to you even when you're not talking. Glancing at you every once in a while. Smile and flirting are the biggest indicators of interest however. On the other hand, if she doesn't like you, you will know it, trust me. She won't particularly glance at you, laugh at all your jokes and most likely won't flirt.