O'Shea saw his side concede three tries in a disappointing display at the Stade Felix Mayol as their hopes of becoming the first team to retain the Amlin Challenge Cup were effectively ended by half time.
But the former Ireland full backs insists the league leaders won't let the result derail their season as they look to push on towards a home tie in the Premiership play-offs.
"I'm not remotely concerned about the squad's confidence as we return to Premiership action," said O'Shea, who was missing star fly-half Nick Evans and skipper Chris Robshaw in Toulon and is convinced his young squad will be stronger for the experience.
"We're disappointed to lose a trophy that we worked incredibly hard to win but we'll concentrate on Wasps now.We are proud of our form at the Twickenham Stoop…and you can read too much into a single defeat.
"Toulon have a huge focus on the Amlin Challenge Cup. They're an outstanding side and will get stronger and stronger, but we'll get stronger too as our young players learn from this and we bring our experienced guys back in as well. We hope Chris and Nick will be fit to face Wasps and there are a number of tough selection decisions we have to make.
"I've got to credit some of our younger guys for keeping going until the bitter end against Toulon. We had people like Will Collier at just 21 coming on at tight-head, Rob Buchanan at 20 had 50 minutes at hooker in that sort of atmosphere against Sebastien Bruno and it was also part of Rory Clegg's continued development.
"A lot of young fellas will have learnt a huge amount out there. They're the environments you have to live and learn in. We'll have learnt a lot of lessons and we'll just focus on the Premiership now."