Why do you think this guy is acting like this?

So me and this guy met about a month ago. When we first met he really got along and he asked me for my twitter. After that he would always say hi to me in the hallway. Then a few days later he direct messaged me on twitter asking to hang out. I couldn't unfortunately but asked him for his number. It took me about a week to build up the courage to text him. I finally did and we hung out with a few other people. When he first got there he started getting closer and finally put his arm around me. Then we were siting in the back of my friends car and he was still all over me. By the end of the night we were pretty messed up and e had his head on my shoulder holding my hand and stuff. After that he still said hi to me and it wasn't awkward. What confuses me is he never seems to put in effort to hang out or even just text me to say hi and have a convo. I don't even know if he likes me or if I'm wasting my time. Honest opinions would be nice.