The result stretched the Addicks' run without a win to 11 games as goals either side of the break from Jason Kennedy and Craig Dawson sunk Powell's team.
Powell said: "Confidence has come back in the last two games, before that it was at a low ebb, and we knew this game was pivotal in terms of the slim chance we had to reach the play offs. But it's not our time this year. We have to finish the season on a high now.
"This result was tough to take because we fashioned a lot of chances on the night, especially in the second half and for their second goal, which killed us, the referee gave a corner when it wasn't a corner.
"These things go against you when you are up against it but I asked the team to give a performance and after the break they did.
"The first goal was always going to be crucial and it went to Rochdale. It was cruel really because I felt we should be walking away with a point and maybe even three."
Source: PA
Source: PA