I can only imagine you got swindled and feel bad about the fact you trusted someone. Don't feel bad, you did nothing wrong. There are sites who take the time to vet their sellers and then there are sites like Fiverr who let's anyone to join with zero check on their credentials.
The entry into selling on Fiverr is so easy that it borders on ridiculousness. Anyone can lie about their location, experience, education, and just about any credentials. Some of them are really clever and mask their fake profile pictures and gig descriptions really well.
Fiverr is so secretive about their vetting process, which I seriously doubt there is anything in writing, that you can't trust it. The seller's level is a joke - I've gotten cheated by ones with thousands of reviews. How they received literally a thousand or more review is mind boggling.
Go back and check again, you'll notice like 99.9% of the million or so sellers all have 5 star reviews. All legitimate businesses have a combination of good and bad reviews, most average around 3/5 or if they are a really great business 4/5 but for a large company with like a million or so freelancers with zero credentials having 5/5 pretty much tells you there is something wrong.
Like I said, you did nothing wrong. I hope you didn't lose too much money. Their philosophy is "We don't care how crappy the delivery was as long as the seller delivered you don't get your money back."