The Millers needed a last-gasp goal from Joe Mattock to earn the equaliser their second-half revival merited against fellow strugglers Reading on Saturday.
It leaves Rotherham three points off the bottom three in the Championship after their 10th draw in 13 games.
Warne was seething after an opening 45 minutes when Reading could have been 3-0 in front, but only had Sam Baldock’s ninth-minute goal to show for their dominance.
But Rotherham – currently 20th in the table – created enough chances to win the game in the second half as the draw ensured they avoided being leapfrogged in the table by the managerless Royals.
“There was importance to this game because losing to them would have dragged us into a dogfight and would have given them a boost,” Warne said.
“But there are a lot of games to go.
“If we fall into the bottom three or four we will just have to fight our way out.
“I have no issue with that. I do have an issue with our first-half performance.
“That wasn’t us. The second half was us. The second half was us trying to get the goals.
“To give Reading three points would have been a massive blow to us.
“We could not have been as bad in the second half as we were in the first. I am pleased with a point.
“We had 26 attempts on goal, 10 on target. Nearly all of those must have come in the second half.”
Warne has rarely had cause to criticise his players since promotion to the Championship last summer.
But the first-half showing warranted some harsh words at the interval and a double substitution.
“I wasn’t happy with anyone in the first half,” he said. “I don’t like taking people off at half-time, but we had to change something.
“I said it to their faces, I could have made 10 changes at half-time.
“Ironically, I was pretty calm at half-time. It’s like when you tell your kids off and you’re that cross that you become calm again. It was like that serial-killer whisper. It was more like that than a rant.
“I wasn’t kicking cups about. I said, ‘That wasn’t us, that isn’t what we stand for, that isn’t what we accept’.”
Match report: Page 2.