Why does my boyfriend think he is a pimp?

so when i first met my boyfriend he was shy, sweet and caring right. Perfect guy who seemed like he didnt have a cocky attitude. well that all changed like 4 months later, now he goes around saying he is pimp **** and hes a hustler and he just thinks hes the coolest creature walking on this planet. what the hell is going through his head? i hate it when he talks like that because a pimp is someone who has a bunch of girls around all the time...correct? or maybe im just uptight about his cocky attitude?