What do I do was he flirting or being nice I cant tell with him?

So there is this guy and I am gonna make it to the point he smiles when I walk into the room he smiles when I look at him he smiles when my parents talk about me he never has his back toward me he is always near me except last sunday!! It was my fault I put him off I guess and so he moved on he is always leaning in and whispering in my ear he even freaking talks to my parents about me is what my mom said!! I mean I know I flirt with him but is it possible he is flirting back because I just cant tell with its hard and I wanna know oh and this girl was being obnoxious and was trying my hardest not to look at him because out of the corner of my eye I could see him starring at me but I looked he smiled shurgged his shoulder walked around and he often does this he will say something incredible stupid and pointless “he has said so we were just laughing over there about this thing” and then that it no more so me and his sister we look at each other like umm okay pointless another time he said kneeling like he was going to propose “ that is reason I wanted tori to be a boy he asked me to buckle his belt and I knew excatly how to do it” again talkin to his sister and we looked like umm okay the thris time he took his psp out of his pocket of his coat and says “oh yes it fits see look” ad again it was like why do you say these pointless things she knows her brother rele well and I think ahe knows when he is flirting and wont tell me or sumn but I wanna know if he was flirting or being nice there is so much more I could say but I juat put in the important stuff thanks so much!!