Whenever psychics say “you are an old soul,” quite often they simply mean:
“you seem older than the average around here”
— or even simply:
“you seem to be more mature than me,”
which could mean anything.
I find that, as a rule, Old Souls tend to know intuitively, and don’t bother to ask. Those who ask, on the other hand, usually hope to be told “Yes you are,” regardless of their own intuitions.