Speaking to the BBC Scotland website, assistant coach Carolan said: "[The nerves were] pretty obvious among the players and staff.
"It was a frustrating night, both forced and unforced errors mounted up. We probably had double the turnovers that we'd normally have, or normally see as acceptable.
"Some of our good work went unrewarded and it just created a level of frustration. There was still enough good stuff there statistically - metres and tackle breaks and line breaks, we were well up there.
"In our review, it was just about managing that frustration, not letting it get to us and just be next action focused. Whatever the next action is - a set-piece or a kick transition - put our effort and our focus into that and nail that. That's how you get back your momentum."
Momentum is something Glasgow will need if the are to overcome the tough challenge Stormers will provide in Saturday's quarter-final at Scotstoun.
"The [last few weeks have] focused our minds again. We focus on what we do well.
"We've looked at our attack stats for the season and we're top three in most of the major metrics there, which shows that our identity is alive when we play to our strengths and to our DNA. It will certainly ask questions of most teams, so it's about bringing that back to the fore again."
George Turner and Kyle Steyn could return to action on Saturday night - and it could be Turner's last game for Glasgow, after it was confirmed he'd be leaving at the end of the season with Japan thought to be his destination.
"He's got a pedigree that certainly we'll miss, but in his absence we've had Johnny Matthews - the top try scorer in the URC for the regular season, which is no mean feat there either.
"We've also got Gregor Hiddleston and Angus Fraser who've been bubbling away in the background. We're developing young guys as well, so while he'll be missed, we'll still bring players through and that's our mandate. If someone leaves, we've got the next guy ready - that's what we're doing."