I need some advice, i only want guys opinions please!?

me and this guy have been great friends for a while.. we hang outt, hes pretty clingy, he hugs me all the time. at school he always talks to me and pretty much flirts. but he flirts with my bestfriend. which just a little while ago he hated her! this confused me. i already have his number like i said we talk all the time. alot of my friends say he likes me but those are girls. (btw he is VERY flirtatious) i need some guys opinions. and at lunch he always walks up to me and will find me if im not where we usually stand and he gave me a nick name and introduced me to his friend by that nick name <3 i like him so much but for some reason a just have that feeling that he doesnt like me and is just flirting. and yesterday when we hung out i heard he was talkkin crap about me so i confronted him about it and told him i never wanna talk to him again. lets keep in mind most people think hes an A hole and he told me before that he doesnt care who hates him. why did hee comfort me and tell me he was sorry and that it really wasnt like that? maybe im just looking for some urance. like i said. IS HE INTO ME or IS HE JUST A REALLY BIG FLIRT.!?!?!? :(