Don't panic. Your body can heal if you get out of its way and support it. You are young and lots of reserves left.
Three things that have helped me tremendously with MCS and food allergies :
1) Detoxing with calcium Bentonite clay--baths and drinking it internally
2) healing gut lining with the herbs slippery elm and marshmellow
3) Meditating twice a day every day to heal the gut