Does he want me or not?

ok im having trouble with this guy, he's one of my brothers friends and hes only 2 years older than me(im 15 hes 17), when ever hes over he always flirts with me like he will always come into my room shut the door and we talk for a while and he always says im such a cutie, sometimes he'll go to me hey jess when are we gonna hook up? but then he laughs and im not sure if he means it or not. also do you think my brother would mind if something would happen between me and one of his best friends? PLEASE HELP!!