I make my teacher angry in Khmer school

I can't forget 2 days in my Khmer school that my teacher was very angry with me . The first time that my teacher angry with me is in the morning at my Khmer school I went to my classroom very late when my teacher wrote the lesson on the board then I walked slowly to my classroom and I went to my sit , I think my teacher didn't saw me went into my class very late but when time to went home teacher asked me "Why you came very late ?" and then I said "I not came late" . When I spoke with my teacher one of my friend said "I saw him walked slowly to classroom when you write the lesson" when she heard my friend said she was very angry to me and blamed me ,this is the first time that my teacher was blame me .
The second time that my teacher was blamed me is in the afternoon , when I drank cocacola with my friend in my class one of my friend ran very fast to me and hit my cocacola can fell to the ground then I blame him and hit his arm . After that my teacher came to the classroom and walk to me she ask me "Why you hit your friend arm ? Do you know you did wrong ? when some one hit you or do something wrong to you you can tell me or director, now you should say sorry to him " I said "Now I know I did wrong but I don't want say sorry to him " and then she blame me and took me to director office ,