Yes MCS is a condition in which chemicals (whether internal or external) have varying degrees of affect on your body systems.
Neurological affectation is the most common effect.
What have you done so far to treat this? Are you aware of Leaky Gut Syndome which most often goes hand in hand with MCS. Is your head always foggy or does it clear? What is your diet like? What is your external environment like? What made you sick to begin with? How much have you read on this subject?
Hopefully these questions will give other posters and myself a good starting point inorder to help you come up with your answers.