Your son is NOT unusual.
At this age stage... they do NOT have 'socialization' mastered yet. They don't even have emotions fully developed yet. They don't even know... the words or vocabulary for how they feel. Nor the communication skills to convey or communicate that. It is taught.
From 2 years old, I taught my kids the 'words' for their feelings and frustrations. As they get older, they get more articulate about it. With guidance.
At this age, they don't even have the ability to analyze social situations, nor accurately.
Emotions and the actions of it... are still very abstract to them. At this age... and even older.
Don't make your son feel bad or 'naughty' about it.
Kids this age are also very territorial... and even at 3 and 4 years old.
Your son, is NOT 'odd.'
He is 2.
He is his age.
At this age, they still do "parallel play" too. NOT interactive play.
He will evolve, as he evolves and develops.
And as you guide him.
But if 'expectations' are not in line with a child nor their age... then, that is when frustration and stress occurs, for both child and parent.
Role-play with him. But don't expect an instant comprehension about it.
It takes, practice. All of childhood.
Do not... feel self-conscious about your son, and him doing that compared to what other kids are or are not doing.
It is not about what others think about him.
He is his age.
He is fine.
Just nurture him.
He is so young, to be astute in skills with social interactions.
Kids learn, like a rock collecting moss.