Why wont the guy who likes me text me back?!?

One of the hottest guys at my school told me he liked me last weekend. We have been texting everyday since. I texted him and he hasnt texted me back for a while and i know he still likes me because my friend recently asked him if he still did. Its been 2 weeks since we've texted and im worried he might be annoyed or mad at me. Also i saw him today and when i walked past he was starring right at me even though he was with his friends. Any advice?!