Regarded as a future prospect the young winger, who joined Blues from Galway United in the summer, has been surprised at how many times he has made it into the first team squad this season.
O'Shea made his Blues debut in the opening game of the season as a substitute against Manchester United at Old Trafford and has since then made the starting line-up in both of the Carling Cup games against Southampton and Sunderland and been named amongst the substitutes for other Premier League games.
He is currently away on international duty with the Republic of Ireland Under 21's squad for their UEFA Championship qualifiers in Georgia and Switzerland.
"It's been great, I love it. Since I went over, everything happened so quickly, and I made my debut quickly enough as well, and that helps," he has said.
"I have been playing the Carling Cup games and on the bench nearly every week, so it's going really well. I am enjoying it, enjoying every minute.
"The week I signed, the manager came out and said, 'He's not one for now, he's one for the future'.
"To be fair, that's what I thought when I was going over anyway. I knew I would have to work hard because of the quality of the players who are there."