Facebook Stalker!??!?!?!?

Last year when I went to school there was this new kid named henry zheng, we slightly knew eachother but we were more of aqcuaintances...so then I moved away and recently he added me on facebook and now comments on EVERYTHING I do! Even when my friends (that he doesn't even know) post on my wall, he comments! And now he always chats with me as if we are bffs, and he asked for my number! I didn't want to be mean so I gave it to him...i don't want to hurt his feelings! He is a really sweet guy, but what should I do???