The Addicks have blown the lead to lose 2-1 in their last two outings, against Sheffield Wednesday at home followed by a south London derby defeat at Crystal Palace on Saturday.
They were well on top at Selhurst Park but missed a host of chances before a late Glenn Murray double sent them on the short journey home empty-handed.
"I said to my group that we have to learn from it," said Powell.
"If you come to a place like Palace, or even if you're playing at home, all people see at five o'clock is the result, they don't see how you played.
"We need to see games out and managing the situation when we come under a bit of pressure."