Charlton manager Russell Slade felt "absolutely sick" after seeing his side concede a late leveller to draw 1-1 at Port Vale.
The Addicks opened the scoring in the first half with a goal from Burnley loanee Frederik Ulvestad but the hosts were given a penalty with five minutes left and Vale top scorer Alex Jones levelled the scoring.
Charlton remain 15th in the table but are only one point above the relegation zone, and fans voiced their frustrations with Slade towards the end of the game.
When asked his feelings on the late equaliser, Slade said: "I feel sick, absolutely sick, but of course the fans will think that's my fault as they were quite vocal in making that point - my fault that we missed six, maybe seven, opportunities and my fault that I gave the penalty away.
"For the away side we've created so many opportunities in the first half against a team that's won five and lost one at home.
"We have to be ruthless with what we do and we're not, and then we don't stick to the game plan as well as we should, we don't continue to do the things that have brought us that success.
"The fans are entitled to their opinion, everybody's entitled to an opinion, but it doesn't mean that I agree with it."
The Addicks face Gillingham away on Saturday in a Kent derby and Slade added: "It's another huge game.
"I'm very disappointed we've missed out on points tonight but it's a game that we will look forward to, it's a bit of a derby game so there will be a bit of an edge to it."
Port Vale coach Andy Smith took positives from the Valiants' second-half performance.
He said: "We started really brightly and I thought we were on to something good but it wasn't to be. In the second half we played better and we looked more of a threat when we stretched it a bit more.
"With our energy towards the end of the game we pushed on, we weren't going to give up and we got the penalty and we'll take a point.
"We brought on two strikers at the end (Rigino Cicilia and Dan Turner) just to go for it, I didn't want the one point, I wanted three, you have to throw the kitchen sink at it sometimes."