Billy Stark's new-look side slipped to defeat in the first two matches in Marbella, when they lost 2-0 to the United States on Friday.
Next up are Canada, and McGeouch is hoping for a much-improved performance.
The Celtic youngster said: "We lost two stupid goals in the game against USA and the boys involved have put their hands up about the mistakes so the result wasn't too disappointing.
"This is a new group who have just come together for the first time. We've had a few training sessions together now which have mainly been about gelling the team and getting to know each other better.
"We have a good squad and get on well but it's still early days for us.
"Everyone is looking forward to the match against Canada and hopefully we can put in a better performance and get a result."
McGeouch, 19, has represented Scotland at every age group since he was 15 and aims to play a big part in next year's Under-21 qualifiers - and has also set his sights on more first-team football at Celtic when he returns from Scotland duty.
He told the Scottish FA's website: "I really enjoy playing for my country and want to be involved when the European qualifiers begin next year.
"For that to happen, I'll need to get as much game time as I can at my club and hopefully I'll be able to stay in Billy's plans.
"The Under-21s is the highest level I've played with for Scotland. It was good to get a wee shot with them when we played Italy but this is a new group and I want to play a bigger role.
"Many of the guys in this squad are playing regular first-team football with their clubs and I want to be playing as much as I can for my club."
Just two months ago McGeouch was knocked unconscious and received a broken jaw during a pre-season friendly match with Real Madrid in Philadelphia.
He added: "Since I returned from injury, I played 30 minutes against Dundee in the league and played in a cup game too.
"I played 90 minutes against USA and it would be great to be involved tomorrow against Canada.
"This trip has helped my match sharpness so hopefully when I return to my club I can kick on and keep pushing for more game time at Celtic and stay involved with the Under-21s."