Is this social anxiety?

Hi, I am in doubt whether my son is dealing with social anxiety disorder. He is only 11 years old. He is shy to interact with others especially with strangers. During the school events and functions, he doesn't show any interest in being a part of it. Last day, their school conducted a small event and he is entrusted with the welcome speech. He tried his maximum to escape from the situation. But his teacher trapped him. I supported him and prepared him for the speech. But while seeing the audience, he couldn't speak a word before them. During that time, being watched by others made him nervous. He told me that he forgot the speech. Is this social anxiety? I have discussed this problem with his teacher. She also has the same doubt. She suggested me to consult a registered clinical psychologist in Toronto. They can help with some behavioral therapies to change his social anxiety disorder. I am planning to take an appointment there. If we don't care this, it will spoil his future. But I would like to know about the duration of this course. Also, Is this course has an age limit? If anybody knows about this, please help me with your valuable replies.