Neither side was able to find the net in a game of few chances, which the Dons ended with 10 men after Mark Reynolds was sent off for a second bookable offence.
Brown said: "I'm biased of course, but I think Aberdeen were the better team. We missed one or two chances but, having said that, our goalkeeper had an excellent save when St Mirren broke away.
"Our old failing of finding the net was apparent. We didn't score, and that's happened too often at home, of which I'm acutely aware.
"We tried three up front in (Johnny) Hayes, (Niall) McGinn and (Peter) Pawlett, with two supporting midfield players in (Gavin) Rae and (Stephen) Hughes.
"We had five committed to attack, with the full-backs encouraged to get forward, but it's just not happening for us in front of goal.
"I think it's unfair to be highly critical of Aberdeen, in view of the effort put in by the players. The commitment, particularly when down to 10 men, was there and we continued to take the game to St Mirren even with 10 men."
Of the pitch, he added: "After the international, Paul Fiske and the groundstaff worked overtime on the pitch. They did everything.
"Arguably St Mirren have the best pitch in the SPL so if it disadvantaged us, it was a disadvantage to St Mirren."
- Sports & Recreation
- St Mirren