Getting screwed over on a payment for a parts purchase?

I might be the one that may possibly had Pay Pal pay the wrong party.
Don't know yet how were going to figure it out, as my Pay Pal page doesn't give me that type of information.
Don't know if i paid john xxxxxx @ xxxxx or johnb xxxxx @ xxxxx
Putting in the mans middle name initial, or leaving it out, in the e mail address, would that make a difference?
Could two different people, have the same e mail, but are different just by the middle initial letter?
Then did i give somebody, the wrong person, a 113 dollar bonus?
If that's the case, he won't be afraid of a phone call. If he takes it and is cordial about the situation, chances are pretty good he's tellin the truth about not receiving the money. Good luck with it Jim, I hope you get it worked out.