Boy trouble ! Please help?

Theres this guy at my school that i recently met and we became good friends in a short time, and he always texted me like ALWAYS but lately he has been actin a little more distant with me and im not sure why... it may be because im the type of person that doesn't get all close and friendly with people til ive known then for like more then 2 weeks. And maybe he might've felt rejected and given up on me but im not sure... but just recently like yesterday and today hes been going back to being all close and stuff but idk what i should do this time.. should i be really friendly back ? but maybe it would make me seem to despite.. but if i do the same thing i did last time he might feel rejected again??? please help !!