Generally, when money is sent to another user it's instantly available. The only time it would be shown as pending is if you sent it to a PayPal which didn't exist, or one which has various restrictions in place (against certain account types, etc) - But generally, or at least as far as I know, it's not automatic.
If you paid through PayPal, via your bank, I'd check your bank statement for the transaction - And whether it returned. If it didn't, I'd contact PayPal via phone and explain the issue to them - Whilst they won't be able to give you details about your friend's account, they could confirm/deny if the payment was sent back to you (and explain where it is).
