Hunt received a blow to the head a split-second after nodding home Jimmy Kebe's cross and had to be taken off as Reading ended Burnley's nine-game unbeaten run to extend their own 100% home record this season.
Coppell said: "It was a brave header - shame he can't remember it. He's got concussion. He got a real clout on the head and I'm not sure he realised where he was.
"Immediately after he came back on he ran like a lunatic about 60 yards, which didn't do him any favours."
It took Reading just four minutes to take the lead through Hunt's sixth goal since his summer move from Dundee United.
Jem Karacan began the move with a pass to Hunt's older brother Stephen Hunt on the left and although his ball into the box was too high for Kevin Doyle it was retrieved by Kebe on the right of the box.
Noel Hunt outjumped his challenger to meet the resulting cross and Karacan also needed treatment having been hit as he made his pass. Karacan recovered but Hunt was obviously still dazed and was replaced by Shane Long 20 minutes later.
The second goal, seven minutes into the second half, was a header from Stephen Hunt which converted another Kebe cross from the right.
Reading made sure of the points with a 64th-minute third from Long, who volleyed home on the run after Doyle had fired in a cross from the left and Chris McCann's 89th-minute header from a cross from the left to make it 3-1 was just a consolation for Burnley.
Burnley manager Owen Coyle, who had won the Manager of the Month award for September, was disappointed his side had not come away with a point.
He said: "There were two teams out there who were trying to pass and move the ball. I'm disappointed to be on the end of a 3-1 scoreline. I'm disappointed with the first goal but I certainly couldn't be disappointed with the way we played in the first half after that.
"We dominated the half and Brian Jensen didn't have a save to make. We should have defended the second goal better when Hunt came in at the far post but Clarke Carlisle was struggling with his back and his movement was limited so that played a part."
Coppell was confident his players had now rid themselves of their post-relegation hang-over.
He said: "We have had two defeats, which gave us a wake-up call. Like all teams who have been relegated, we have had to re-adjust. We are re-adjusting but we are still very much a target for a lot of sides."