I hope he doesnt lose interest....

This guy and I have been dating for quite some time and he wants me to become his girlfriend but I told him that I wasnt ready just yet.We see eachother twice a week and thats only on the weekends which is cool. He lives an hour from me and he always comes to my town on the weekends to spend time with me then leaves sunday night. In this relationship we started taking things really slow. We never done anything physical including a kiss till after a month. This past sunday we did something unusal than our normal kiss/convo thingy. On Sunday things got a bit heavy. We couldnt stop touching eachother and actually starting kissing, etc. one thing lead to another and well we didnt have sex but other things went down that I did to HIM and not vice versa b/c at the moment I felt guilty and didnt want him to take full advantage of me w/o commitement. "You cant have your cake & eat it 2"

Now I feel a bit guilty because we arent bf/gf and I did something I wasnt suppose to do i dont think. I feel he got a piece of me and we arent fully commited. I dont want him to think "Oh, I got what i want and now im out" Guys love to chase and once they get what they want, they lose interest. I really like this guy ALOT and I want to know how can i turn the tables again into having him thinking if I like him or want him like in the beg.? At first he would call and I would not return his phone call or callback 30 min laters. Staying busy is key or atleast pretend your busy. That way the guy thinks he is your "last" priority and you "act" like you dont need him or atleast make HIM think that...right?