What does he mean?

So I’ve liked this guy for a while, a girl told him I liked him and he thought I didn’t know that he knew. So when I saw him for the first time again with the new information, I avoided him. If we talked it was short answers, and eventually he stopped trying and we didn’t talk really at all. To make me feel better about him knowing (and me thinking the absolute worst of this outcome) they made fun of him and I would force myself to laugh. It didn’t feel right and I said sorry he was super nice and said he understood since we didn’t talk as much because of a class we had together. And ever since I said sorry he stares for long periods of time. Sometimes he would stare with a straight face and then smile (when I’m not looking) or sometimes he would look me up and down again when I’m not looking. What does this mean?