You're enemies, but he's in love with you, he doesn't like it when other guys confess their love to you, you're surprised by his behavior since he's become a little "nice" to you, but that's his way of showing that he cares, you think that he's crazy and this is another one of his tactics to irritate you, but he still tries to please you, sure, he still irritates you a little, but that's because he doesn't know how to show that he loves you.

"Hey, stupid." He says as he passes by.