He says everythings okay, but why does it feel that it's not?

okay ther is this guy that i like. later me and him become friends. One day my friends writes him a threat letter to him, and he blamed me. I told him everything, that i even liked him, that it wasnt my fault, and that i dont know why my friend sentit to him. He believed me and forgave me and friend. A couple of days later back in school, i noticed a change in him towards me, that he's not saying hi to me anymore and not sitting next to me on the bus to school. It was an awkward bond between me and him. So then i talked to him and he said that he's not mad at me and that were still friends, that everything was okay between us. but today i felt that there was still something wierd between us and i dont kow what's going on in his head. please i need help to make this friendship last between me and him, and that there will be nothing wierd between us..........................