It’s the subjunctive that’s causing me fits today.
Okay, so these phrases are correct:
“If I were a professional”
and
“I wish I were a professional.”
But what about this one:
“I played well, as if I were a professional.” Should it be were or was?
I’m assuming you are not a professional and you are not proposing a possibility in which you might be.
I say stick with “were.”
You could also say “had been.”
“If I was” is used for conditional statements. Your examples here are properly subjunctive.