DS has just turned two and he has had a language spurt in the last couple of months, with his sentences getting more complex. However, he'll often say "You want that one" (for example) instead of "I want that one", or "You bumped your head" when he means that he's bumped his head. If I prompt, "ah, but what does DS need to say?" he'll respond with the correct answer, i.e "I bumped my head".
Is this a normal development? He doesn't have a sibling to copy (so therefore he hasn't really experienced any "Mine!...No, MINE!" type arguments!) and he's used to hearing us talking to and about him, so he does hear 'you' and 'yours' a lot more than 'I', 'me' or 'my'. I haven't heard any other toddlers talking like this, though!