Song's comments after Arsenal's disappointment at allowing Leyton Orient to force the Gunners into an FA Cup fifth-round replay.
The Cameroon midfielder was the only member of the starting XI which had beaten Barcelona included at Brisbane Road on Sunday as manager Arsene Wenger made full use of his squad, which included a debut for teenage Spanish centre-half Ignasi Miquel.
It had all just about been going to plan after Tomas Rosicky headed in his first goal in more than a year at the start of the second half.
However, with just a minute of normal time remaining, substitute Jonathan Tehoue earned the battling npower League One side a money-spinning replay.
Wenger admitted his men, who needed two attempts to see off Leeds in the third round, could have done without another fixture, as they continue to fight on four fronts.