The 25-year-old stopper denied Stephen Quinn on two occasions and also kept out efforts from Jamie Ward, Henri Camara and Matt Kilgallon as Forest maintained their unbeaten Championship record away from home.
Kelly, who took charge of the visitors after manager Billy Davies was taken ill prior to the game, said: "Campy was brilliant. He made three or four really good saves.
"But he's been like that since the start of the season. He's been very consistent.
"He's a first-class lad and a first-class keeper. He works hard on the training ground and he's done well for us.
"He's had a couple of years in the wilderness but his form has been brilliant, and if you see us on a regular basis you would see that he's been super from the very first day of the season."
Kelly was pleased to come away from Bramall Lane with a point despite seeing his side fail to reproduce the free-flowing football that led to comprehensive victories over Doncaster and Leicester.
"It wasn't the best game you'll ever come and watch," he admitted. "But sometimes you just have to play what's there.
"It was a bit of a miserable old night and Sheffield play a little bit more direct than Doncaster, for argument's sake, or some of the other teams do.
"At the City Ground we have been passing people off the park, but away from home you have to set up differently and face different types of challenges.
It was scrappy and it wasn't very pretty but we're pleased to get the point."
On the subject of Davies' health, Kelly added: "Billy's got a flu virus.
"He's struggling away, he's not been well for a couple of days and the advice was to stay away."
United number two Gary Speed also handled the post-match media duties in place of Kevin Blackwell.
And the former Wales midfielder had mixed emotions after seeing his side fail to make the most of their second-half dominance.
"Their goalkeeper played well and made some good saves," said Speed.
"We made him work a bit more in the second half, but we just lacked that little bit of luck or quality to finish it off when the opportunities arose.
"It's something to work on for Saturday (when the Blades entertain Crystal Palace), but we've got a lot of positives to take from the game. If it wasn't for the keeper it could have been two or three nil."
The result extends United's unbeaten run to five matches and they remain in touch with the play-off positions despite a poor start to the campaign.
"Hopefully we can carry it (the unbeaten run) on for as long as possible," Speed added.
"You look at the scores in the league every week and there are surprises so if we keep our little run going and keep that momentum we'll be in and amongst it."