McInnes admitted his team were not at their best despite extending their unbeaten run to six matches with a 1-1 draw with St Mirren.
Steven Thompson opened the scoring for the home side in the second half before Peter Pawlett equalised for the Dons with six minutes to go.
Aberdeen remain fourth in the Scottish Premiership table with 14 points from eight matches.
And McInnes knows his men can perform better - but accepts that his tactics were awry.
He said: "The mistake that I've made is that the system didn't really suit us in the first half.
"Equally, I think the players are better than what they showed tonight.
"We are delighted to still pick up a point on the road while not being at our best."