This guy was interested in me at the gym and he added me on Facebook and then we started talking and he got my number and we started texting. I saw him at the gym and he kept passing me but never talked to me... he just sometimes stared and looked away and after that I text him but he never texted me back and I don't know what to do? Keep texting him even without a response by him or just wait?

I think you wait until he makes a move. Why chase a stranger when you have no clue what his motives, or intentions are?

How old is he?

Don't talk to them! Not until he makes a move.. or you make a move

I'm a girl ahah and I say just wait