Aberdeen came close to scoring on numerous occasions - captain for day Jamie McAllister hit the post, with young strikers Darren Mackie and Scott Michie both missing a couple of gilt-edged chances each.
Paterson told the official Aberdeen website: "I'm really unhappy to have lost this game as I thought we created enough chances to win two games, but just didn't show enough composure in the box.
It was encouraging though to see the new lads doing well, particularly Paul Sheerin who linked up well with Chris Clark in the first half. But we must cut out the silly mistakes at the back as they cost you games.
"It was a good learning experience for the like of Ross O'Donoghue. After all, it's not every day you're faced with a player of the stature of Stefan Effenberg.
Overall though, I suppose I can't be too down, even if I do think this was one of those games that got away from us."
Aberdeen Teamsheet: Esson, Rutkiewicz, Deloumeaux, McAllister, McNaughton, Tosh, O'Donoghue, Sheerin, Clark, Michie and Mike. Subs: Preece, Derek Young, Payne, Tiernan, Duncan, Fabiano and Mackie. (All used except Preece)