is he cheating?

My bf and i have been together for over 4 years. We started out so young we're only 17. Ive let a lot of things slide because im still so in love with him. I know hes growing and we're so young to be so serious. Yet im driving myself crazy with this new girl thinking hes cheating. First he refuses to share his location, he changed his phone password after i asked him to share his location. Hes always on his phone & I feel neglected because he wont even touch me now. He doesnt want to hang out very much & always wants to be alone. Today he went out all day & didnt even text me till 7 . What do i do ???