Hi. You don't say if you're a child or an adult. <<EDIT - I read some of your other messages and see you're a pupil rather than a teacher>>
I acquired PTSD through being bullied by another adult at work. My opinion is that good, targeted therapy plus some kind of closure on the bullying issue is essential before the panic attacks can stop. It is alos important to have your condition recognised as PTSD (and I take it you have been diagnosed with PTSD). So many health professionals look to their lists of illnesses and fail to diagnose pstd. Then they treat you for something you haven't got, and they don't treat you for what you do have!
After diagnosis you need recognition and support from those who are there to care for you, which means family and the school. In my opinion you should not be made to have contact with the child who assaulted you, unless YOU want to do that. If it is not your choice, it sounds like there is something seriously wrong. Do the "officials" who allow you to share the same space know about your condition? Are you in a "civilized" country with health and safety laws?
I know that ptsd can be very distressing for you and those who love you, but I now realise that being diagnosed gave me a distinct advantage over all those people whose heads are screwed up, but who refuse to believe they need help. Their conditions often deteriorate beyond recovery.
Most of the improvement in your condition is going to have to come from within you. Others can guide you, but you are the leader. You can be really strong, stronger than everyone around you. You can learn to cope with the most difficult situations and it will be natural for you.
Most of it hangs on your view of life, other people and yourself. When you accept that can control only yourself, and merely influence other people, and that there are some other people who will never do what you would like, you learn not to be disappointed when they do things you don't like.
You need to learn that it is okay to feel angry, and to express your anger, albeit in a civilised and non violent way. Never bully your bully, or you become like them. You need to learn to think rationally and objectively about your fears. Some fears are entirely justified and you do well to make your decisions according to them. Others are not so rational, and they constrain your activities. Sometimes you will have to just do the thing you're scared of. When you have done it one time, and you realise that you did not come to any harm, you will be less fearful next time around. And as you become less fearful, the panic attacks will slowly decline.