how to know it's not a rebound?

how does one know when meeting someone that the person they just met is not just a rebound?

I guess I should clarify on my situation. I went to a dance club at my school and this girl asked me to dance. She seemed like a really cool person and we both seemed to take interest in each other. I got her number before leaving. I was just thinking to myself whether I really wanted to get involved with someone, because I just got out of a bad relationship not too long ago. I don't want to hurt someone by having them be a rebound. But how can I know that's the case? I don't miss my ex if that means anything.