What are the embarrassing things about sending the wrong message?

My best friend has the same surname as the class teacher. I sent a text message to my best friend, saying, "Take a leave for my teacher, and tell her that I have a big aunt and a stomachache. I went to the Internet cafe to play a game. "

After a while, the teacher texted back and said, "Can you still play games with a stomachache?" I will check you when I study at night. "

I see, oh, hey, how did you send the last message to the teacher!