Whyd he want me so much to begin with then weeks later hes basically acts like he did nothing?

How has your behavior been towards him? If you're acting like nothing has been happening, he'll probably just act off of that. Now, I'm not saying it's your fault he's acting this way, because there could be a number of things that could play a role in his behavior. Try asking him what's going on the next time you see him (or you could call/text him), and maybe he'll give you an answer to whatever questions you have. Hope this helped.