There are a lot of young kids suffering from social anxiety. From what I have seen, social anxiety gets pretty bad during or after puberty in a child. Many people suffer the most in high school. Also there can be a lot of young kids like you mentioned. There could have been a traumatizing event that happened in the child's life that made them act the way they do now.

Online tests are not always accurate but you should have an idea if the child has some sort of social disorder. If they are terrified of speaking to people (especially strangers) then that is a good indicator.

I would recommend taking the child to a professional.

Its really down to adults having impossible expectations of their children. For every failing their child has, their must be a medical reason, and a pill that can change it. This is just not the case. When i was young, parents would blame everything that was troubling their child, on their tonsils and adenoids, the hospitals in the UK had a production line for taking them out. I went through it myself, as did most of the children in my class at school. By the nienties, it had all stopped. When parents mad the suggestion of tonsils adenoids removed, doctors sent the parents for counceling.

For a while, i did voluntary work, teaching reading and wrting to adults, who were illiterate. Every one of them claimed to suffer from dyslexia, which left me firstly wondering, that if they had a medical diagnosis that said they couldnt learn to read or write, why were they turning up, to learn to read and write. One guy I taught, i was really pleased, because he was getting it all really quickly, and by the end of the session, he could read Cat, Sat, Pat, Bat, Hat, he was doing well, next session, a few days later, it had all gone. I told my supervisor, a qualified teacher with thirty years experience, she said to me "he had memory problems, he will never learn to read or write" when i mentioned to her, the ones with Dyslexia, she said "dyslexia, middle class thick"

Its actually sad, that our expectation are so high, that if a child cant do something as well as everyone else in their class, we want a medical diagnoses, to say their is a reason they cant do it.

I rent houses our for a living, and was once phoned by a woman, who told me she was a single mother with a disabled son. I arranged to meet her at the house, but i told her, this house hadnt been in any way converted to be suitable for disabled. She told me that was fine. I expected her to arrive pushing a wheel chair, she didnt both her and her son arrived at the door, and both of them looked fine to me, he son behaved very much like i did at his age, high energy, he was all over the house, then he ran into the garden, where he picked some flowers and gave them to his mom. She told him not to pick flowers, then explained to me, that he was disabled, with ADHD.

What chance does that child have, when his mother is going to tell him for the rest of his life, that he is disabled, with ADHD, He is not going to try his best at anything, because he is being told, that not much is expected from him.

Had such a thing existed when i was young, my mom would have got me diagnosed with that. Today, a more common thing is to get diagnosed with autism. When i was young, autism was a serious mental condition, today it means you are bottom of your class.

I wouldnt bother about social anxiety disorder, lots of children are shy, its what they excell in.