If you offer someone a gift and they don't take it, it could mean one of a few things.
- They're not comfortable accepting any kind of gift from anyone.
- They don't want to feel like they 'owe' you anything.
- They're embarrassed and don't respond the way they'd like to. (They generally think pretty stupid afterward.)
- They don't like you enough to want to take a gift from you.
Now that you've offered him a gift, he certainly should know that you like him. I think you're going to have to wait for a while and see what he does next. He's either going to make some kind of gesture to show you that he likes you too, or else he's going to keep his distance.
I think you'll know if he likes you or not soon enough.