For the most part, the policy on the PSN (and a lot of other digital outlets) is a 100% "no refund" policy. When you pre-order something, the price is locked in, your bank account is drained, and you're committed. That seemed to be the case when people pre-ordered The Last of Us Remastered on PS4 digitally for $60, but there was one problem -- the game was discounted by $10, and said people didn't get any word of a refund.
According to Sony VP of Publisher and Developer Relations Adam Boyes though, everyone "should" be getting a $10 refund in the next "5-7 days." So don't fret if you jumped the gun.
Adam Boyes [Twitter]