Town boss Joe Royle felt the "hubbub" and "hoo-hah" about Tommy Miller's twice-taken penalty led to his side switching off and letting Paul Hart's side back into the game.
Royle also thought his defence had a edgy afternoon: "We never really recovered from the hubbub about the penalty and the hoo-hah that followed. We switched off.
"We came back strongly in the second half for a good equaliser but we picked the wrong day to have a nervous time defensively.
"Every time the ball was in their box I thought we'd score but every time the ball was in our box I thought they would score.
"At 2-0 up we were cruising. Pablo Counago could have had a first-half hat-trick.
"The other results were not too damaging. We are still in it.
"It was a hard game to referee. One of their players was lucky to stay on the field after being booked while Forest must feel that the twice-taken penalty was contentious."
Forest boss Paul Hart was unimpressed with the way the decision to retake the penalty was made: "Darren [Ward] must have moved forward but he saved at the foot of the post. How you can get your body in that shape I don't know.
"I am not disputing anything but the linesman did not flag. He used a buzzer to contact the referee which meant that no-one else knew what was going on."
"We've performed better in many games but in view of the importance of the occasion this was a terrific result. I consider Ipswich to be the best side we have played. If they hadn't had such a bad start to the season they would have been in the play-offs.
"We have a young side who have had a lot of experiences this season but they have handled everything that has been thrown at them. We have come through enough today.
"It was a great game for the neutral to sit back and enjoy but certainly not for a manager in the dug-out. You can smile afterwards."