If you have a counselor (guidance or other) or nurse at your school, I would suggest talking to them. I can understand that talking to your parents might be too much right now, but it would also help to have someone supportive who understands. If you feel safe with that teacher, you could also talk to them, and even just explain that what they did, calling out your name, helped bring you back. A lot of students have trouble with focus, and teachers will be more understanding about any confusion over coursework, etc, if they know that you aren't just ignoring them, that you actually can't understand. If none of those supports feel safe to you, other options are your family doctor, or any other supports in your life.
Good luck, keep us posted!!