DS2 was diagnosed with 'mild autism' when he was eleven. This after a very long journey for him and us, badgering for a referral from when he was 8 - we knew something was not right when he was a toddler - he would hide / run away from crowded / busy situations. I could NEVER sit down and have a cup of coffee at a mum's gathering - he always wanted to be 'out of' the crowd. He walked on tiptoes, avoided eye contact, wet the bed at night until he was past seven years, didn't cope at school socially, couldn't sit and engage at family mealtimes, would physically shake with nerves just packing his bag for school in the morning ... There were many, many signs. Initially it was a case of 'Don't believe you / you are over-anxious parents' then, what have YOU done wrong, before proper investigation.
We learned that he is very sensitive to noise - even the clatter of cutlery at a family meal-time was / is hard for him. His senses are very acute so smell, touch, taste etc. are all affected. He approaches life with a very busy - very intelligent mind, but very stressed by 'normal' life. So, like the apparently serene swan, he is paddling furiously just to stay afloat and he tires quickly.
Despite his diagnosis, he was never offered any further support re building social skills - it seems he had this 'label' from the authorities and that was all. He now suffers anxiety and depression that impact on him being able to sustain full-time employment.
For years I was made to question my own parenting. The fact that we had three other healthy, happy children made me able to believe I was not a terrible parent, but it has been a hard road. I think we have had to be 'pushy' parents along the way - and now, given the dire state of mental health support, we continue to have to jump up and down to get things moving for him ... Grrrr.