How to know all he wants is sex?

Am 20 and hes 29, we met on the internet, a year and half ago, on the first date, he took me to his house, he tried to have sex with me but I refused, he then took me to the beach and then the restaurant to eat.he then dropped me off home, the second date he took me to his house, we watch a movie and he tried to have sex with me again and I said no, cause am still a virgin and that am not ready..

       On the 3rd date he tried the same thing, I still said no, then he said am wasting his time so I shouldnt call him again, I said ok, he didnt even bother to see me off, so I left and I didnt call him like he asked and after a month and half , he called me again acting like nothing has happend, and he wanna see me and all that
     I realised I like him, even after everything he keeps doing, he smokes weed too, he been smoking for 10years and I think its part of the reason why he acts the way he does, lately, he seems to have changed, he calls me like every day, night, and we talk for like hours, he tells me his problems, he shares his weaknesses with me, and advice me and help me with my school works... He stopped asking me for sex, and says hes gon do what makes me happy..
  I want to know if he really changed, he really likes me ? Or is still after sex? Please help me and desperate to know, before I lose ma virginity to the wrong guy