Did he ever immediately respond to your texts/calls? I read your question several times, and it doesn't sound needy, it IS needy. Now most single guys will initially respond quickly to that, because it's such an easy in. However, it's not much of a challenge, and guys always need a challenge. The only other reason a guy would keep responding immediately to a needy girl would be that he feels he has let another down in the past and is trying to make up for it now. In that case, he would be projecting some need of his own onto you, but it's not really YOU he's responding to. Is that what you want? You cannot make somebody need you, so the only thing left to answer is why do you need this guy to need you so much?