Waiting for a diagnoses

Hello,

My Son who has just turned 4 is on the waiting list for an assessment for autism. He has traits of autism but i think I'm in denial. Some days i will think his absolutely fine, then other days I'm thinking okay he is... 

is this normal for a parent to feel like this? I just want to know now if he is or not, it won't make any difference because his perfect but it would explain why he reacts the way he does to certain things.

Could someone explain autism to me? I'm pretty new and still trying to educate myself. 

Thank you!