Derek McInnes viewed his Aberdeen team's as two points dropped after the Pittodrie visitors recovered from two goals down.
"We had so many chances and we were so wasteful," said the Dons boss after watching Kenny McLean score from the spot to complete the Saints comeback.
"We were very dominant. There was loads to like about us but it counts for nothing if we don't win.
"We lost a poor goal straight after our second and that encouraged St Mirren."
Aberdeen were playing their fourth game at home in 11 days. They had registered Scottish Premiership wins over Ross County and Inverness and a 4-0 League Cup victory over Livingston.
A win over the Buddies would have lifted them to fourth in the table and that looked likely when Mark Reynolds cracked in the opener just before half-time and Peter Pawlett added a second in 56 minutes.
|Aberdeen manager Derek McInnes|
|"We had them where we wanted them and we allowed them back into the game."|
Backed by more than 10,000 fans, Aberdeen should have been further ahead by then, but their profligacy and the goalkeeping heroics of Marian Kello kept Tommy Craig's strugglers in it.
They pulled one back within a minute of Pawlett's strike through Callum Ball and as nervousness spread around the stands, Reynolds handled a cross into the box and McLean scored the resultant penalty.
"We had enough know-how out on the pitch to see it out," McInnes told BBC Scotland.
"We're disappointed as a team. It's not just the boys at the top end of the pitch.
"We should be taking more responsibility to score more goals, regardless of their keeper making good saves.
"The majority of players had an opportunity to score tonight.
"We had them where we wanted them and we allowed them back into the game. We're a good side but we have to find ways to win. It should have been four wins in a row.
"We have chucked away two points but you've got to credit St Mirren. The response was good from their point of view."