As caregiver mentioned it is not possible to predict. I had a somewhat similar injury like you 4 years ago and noticed after few days that my smell and taste was distorted but not completely lost. Very bad smell and as far food I can taste only the 4 basic tastes.
Now the good news is mostly I am back to normal (about 90%). I can make it 100% by taking some meds. But I suggest you avoid those meds since it is very addictive. No one knows why it works but I take those meds for my dizziness, head pressure symptoms (those are the constant terrible symptoms I still have most part of the day).
What you can try is B12 which I did take for a long time. Another thing called Neurofeedback (biofeedback) - LENS also works for me. Not sure it is available in your country. Regardless you can only try and my smell started to come back after a year and half.
This site and doctor is a specialist in smell disorders and you can get lots of information.
http://www.tasteandsmell.com/
An intersting question, and the answer is "maybe yes and maybe no". The sense of smell is moderated by the first cranial nerve, and a swelling of this nerve can deprive a patient of the sense of smell. This can happen due to infection, neuroma, or inflammation. When the nerve settles down the sense of smell may return. More importantly this accident took place on school grounds and your medical treatment in the United States is the responsibility of the school. I would suggest you keep good medical documtation and see an attorney.