Chris Wood struck midway in the second-half for Forest's winner.
Glasner later said: "Very frustrating and very disappointing. It was a again a very close, tight game. At the end it was one tiny moment that decided the game and it's always against us.
"The players are fighting hard. Yes we know our football right now is not the best, but we created chances and twice hit the post.
"We have had better times in our life together. We have to support each other to get the chin up and get ready for the next game.
"It's not the time to blame anybody, I saw the players working hard from the first minute to the last. When we conceded the goal I thought we were better in the game. We lost the momentum and confidence. But we came back into the game and they made two unbelievable saves.
"It's tough at the moment to be honest. But the character of the players, the hard working. Yes it's disappointing but nobody is blaming anybody. The chemistry is good in the dressing room. We need the confidence and to get that we need to score goals.
"We will work hard to get this, to get the goals and the win.
"It's not about too much tactical things, I see no problems regarding the tactics. Very often we are in the final third and making the wrong decisions. This is due to a lack of confidence. We are humans.
"It's time for hugging the players, not for kicking them."