Eriksen, who also collapsed during an international match in 2021, caused widespread concern when he clutched his chest and fell in the 65th minute of Sunday's game.
The 34-year-old playmaker has returned home and said he is recovering well.
"It has been a tough day for all of us, but fortunately Christian is doing well and is back home with his family," Riemer said on Monday.
"Now he and the players need to have some peace to process the experience, so that everyone can recover from the shock.
"In a difficult moment, everyone showed a beautiful unity, which I think is what we should remember about this evening."