I have MCS, so I know how difficult it can be. Immunotherapy can sometimes help people, there is not a specific treatment for perfume intolerance, but around ten years ago, and at my worst, my allergist gave me immunotherapy, he gave me a mixture of everything he knew I had a problem with, pollen, mold etc. The reasoning being that he felt that if he resolved those issues everything else would settle down, and it did, it worked. So, maybe you could speak with your doctor and see if they can do something for you as it must be very difficult being at school all day with this problem.
A temporary solution which works for me is to use homeopathy drops which you can buy online, they are called Allergena Fragrance (Allergy relief from fragrance, smoke and pollutants) I can promise you that these drops work, and work well, so maybe you can get hold of these drops until you have an appointment for immunatherapy.
Samantha, 45 yrs
Stopped smoking Jan 2013. Diagnosed Left sided UC, 8th Feb 2014.
Pentasa 3.5g daily, Vit D, Multivitamin, Vit B12, 500mcg Molybdenum
Gluten, Dairy and Sulfite free.